521972539 has 8 divisors (see below), whose sum is σ = 602920368. Its totient is φ = 446607360.

The previous prime is 521972533. The next prime is 521972543. The reversal of 521972539 is 935279125.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 521972539 - 2¹⁵ = 521939771 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 521972495 and 521972504.

It is not an unprimeable number, because it can be changed into a prime (521972533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1395462 + ... + 1395835.

It is an arithmetic number, because the mean of its divisors is an integer number (75365046).

Almost surely, 2^521972539 is an apocalyptic number.

521972539 is a deficient number, since it is larger than the sum of its proper divisors (80947829).

521972539 is a wasteful number, since it uses less digits than its factorization.

521972539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2791325.

The product of its digits is 170100, while the sum is 43.

The square root of 521972539 is about 22846.7183420289. The cubic root of 521972539 is about 805.1606685206.

The spelling of 521972539 in words is "five hundred twenty-one million, nine hundred seventy-two thousand, five hundred thirty-nine".