942821 has 4 divisors (see below), whose sum is σ = 1028544. Its totient is φ = 857100.

The previous prime is 942811. The next prime is 942827. The reversal of 942821 is 128249.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 942821 - 2¹⁴ = 926437 is a prime.

It is a super-2 number, since 2×942821² = 1777822876082, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (942827) 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 3 ways as a sum of consecutive naturals, for example, 42845 + ... + 42866.

It is an arithmetic number, because the mean of its divisors is an integer number (257136).

2⁹⁴²⁸²¹ is an apocalyptic number.

It is an amenable number.

942821 is a deficient number, since it is larger than the sum of its proper divisors (85723).

942821 is a wasteful number, since it uses less digits than its factorization.

942821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85722.

The product of its digits is 1152, while the sum is 26.

The square root of 942821 is about 970.9897012842. The cubic root of 942821 is about 98.0565063545.

It can be divided in two parts, 9428 and 21, that added together give a palindrome (9449).

The spelling of 942821 in words is "nine hundred forty-two thousand, eight hundred twenty-one".