509925921 has 4 divisors (see below), whose sum is σ = 679901232. Its totient is φ = 339950612.

The previous prime is 509925917. The next prime is 509925973. The reversal of 509925921 is 129529905.

It is a happy number.

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 509925921 - 2² = 509925917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (509925121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 84987651 + ... + 84987656.

It is an arithmetic number, because the mean of its divisors is an integer number (169975308).

Almost surely, 2^509925921 is an apocalyptic number.

It is an amenable number.

509925921 is a deficient number, since it is larger than the sum of its proper divisors (169975311).

509925921 is a wasteful number, since it uses less digits than its factorization.

509925921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169975310.

The product of its (nonzero) digits is 72900, while the sum is 42.

The square root of 509925921 is about 22581.5393850818. The cubic root of 509925921 is about 798.9182885555.

The spelling of 509925921 in words is "five hundred nine million, nine hundred twenty-five thousand, nine hundred twenty-one".