521972157 has 12 divisors (see below), whose sum is σ = 809589696. Its totient is φ = 298269720.

The previous prime is 521972149. The next prime is 521972179. The reversal of 521972157 is 751279125.

It is a happy number.

It is not a de Polignac number, because 521972157 - 2³ = 521972149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521972117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1775269 + ... + 1775562.

It is an arithmetic number, because the mean of its divisors is an integer number (67465808).

Almost surely, 2^521972157 is an apocalyptic number.

It is an amenable number.

521972157 is a deficient number, since it is larger than the sum of its proper divisors (287617539).

521972157 is a wasteful number, since it uses less digits than its factorization.

521972157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3550848 (or 3550841 counting only the distinct ones).

The product of its digits is 44100, while the sum is 39.

The square root of 521972157 is about 22846.7099819646. The cubic root of 521972157 is about 805.1604721045.

The spelling of 521972157 in words is "five hundred twenty-one million, nine hundred seventy-two thousand, one hundred fifty-seven".