436921 has 3 divisors (see below), whose sum is σ = 437583. Its totient is φ = 436260.

The previous prime is 436913. The next prime is 436957. The reversal of 436921 is 129634.

The square root of 436921 is 661.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 129634 = 2 ⋅64817.

It can be written as a sum of positive squares in only one way, i.e., 346921 + 90000 = 589^2 + 300^2 .

It is not a de Polignac number, because 436921 - 2³ = 436913 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (436621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 331 + ... + 991.

It is an arithmetic number, because the mean of its divisors is an integer number (145861).

436921 is a Friedman number, since it can be written as (3+94*(6+1))^2, using all its digits and the basic arithmetic operations.

2⁴³⁶⁹²¹ is an apocalyptic number.

436921 is the 661-st square number.

436921 is the 331-st centered octagonal number.

It is an amenable number.

436921 is a deficient number, since it is larger than the sum of its proper divisors (662).

436921 is an frugal number, since it uses more digits than its factorization.

436921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322 (or 661 counting only the distinct ones).

The product of its digits is 1296, while the sum is 25.

The cubic root of 436921 is about 75.8812202741.

Multiplying 436921 by its sum of digits (25), we get a square (10923025 = 3305²).

Multiplying 436921 by its product of digits (1296), we get a square (566249616 = 23796²).

The spelling of 436921 in words is "four hundred thirty-six thousand, nine hundred twenty-one".