521034921 has 36 divisors (see below), whose sum is σ = 872209104. Its totient is φ = 297187200.

The previous prime is 521034919. The next prime is 521034931. The reversal of 521034921 is 129430125.

It is not a de Polignac number, because 521034921 - 2¹ = 521034919 is a prime.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (521034931) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 19506 + ... + 37716.

Almost surely, 2^521034921 is an apocalyptic number.

521034921 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

521034921 is a deficient number, since it is larger than the sum of its proper divisors (351174183).

521034921 is a wasteful number, since it uses less digits than its factorization.

521034921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18262 (or 18242 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 521034921 is about 22826.1893666026. The cubic root of 521034921 is about 804.6782768498.

The spelling of 521034921 in words is "five hundred twenty-one million, thirty-four thousand, nine hundred twenty-one".