904072021 has 2 divisors, whose sum is σ = 904072022. Its totient is φ = 904072020.

The previous prime is 904071991. The next prime is 904072073. The reversal of 904072021 is 120270409.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 779191396 + 124880625 = 27914^2 + 11175^2 .

It is a cyclic number.

It is not a de Polignac number, because 904072021 - 2²³ = 895683413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (904072321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 452036010 + 452036011.

It is an arithmetic number, because the mean of its divisors is an integer number (452036011).

Almost surely, 2^904072021 is an apocalyptic number.

It is an amenable number.

904072021 is a deficient number, since it is larger than the sum of its proper divisors (1).

904072021 is an equidigital number, since it uses as much as digits as its factorization.

904072021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 904072021 is about 30067.7904243062. The cubic root of 904072021 is about 966.9433026071.

The spelling of 904072021 in words is "nine hundred four million, seventy-two thousand, twenty-one".