42941809 has 3 divisors (see below), whose sum is σ = 42948363. Its totient is φ = 42935256.

The previous prime is 42941797. The next prime is 42941831. The reversal of 42941809 is 90814924.

It is a happy number.

The square root of 42941809 is 6553.

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.

It can be written as a sum of positive squares in only one way, i.e., 14554225 + 28387584 = 3815^2 + 5328^2 .

It is not a de Polignac number, because 42941809 - 2⁵ = 42941777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42941849) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 3277 + ... + 9829.

It is an arithmetic number, because the mean of its divisors is an integer number (14316121).

Almost surely, 2^42941809 is an apocalyptic number.

42941809 is the 6553-rd square number.

42941809 is the 3277-th centered octagonal number.

It is an amenable number.

42941809 is a deficient number, since it is larger than the sum of its proper divisors (6554).

42941809 is an frugal number, since it uses more digits than its factorization.

42941809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13106 (or 6553 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The cubic root of 42941809 is about 350.1816988539.

Multiplying 42941809 by its product of nonzero digits (20736), we get a square (890441351424 = 943632²).

The spelling of 42941809 in words is "forty-two million, nine hundred forty-one thousand, eight hundred nine".