399255505525 has 12 divisors (see below), whose sum is σ = 512148442500. Its totient is φ = 308390458880.

The previous prime is 399255505513. The next prime is 399255505547. The reversal of 399255505525 is 525505552993.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 137334961 + 399118170564 = 11719^2 + 631758^2 .

It is not a de Polignac number, because 399255505525 - 2¹⁵ = 399255472757 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 275347900 + ... + 275349349.

It is an arithmetic number, because the mean of its divisors is an integer number (42679036875).

Almost surely, 2^399255505525 is an apocalyptic number.

It is an amenable number.

399255505525 is a deficient number, since it is larger than the sum of its proper divisors (112892936975).

399255505525 is a wasteful number, since it uses less digits than its factorization.

399255505525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550697288 (or 550697283 counting only the distinct ones).

The product of its (nonzero) digits is 15187500, while the sum is 55.

The spelling of 399255505525 in words is "three hundred ninety-nine billion, two hundred fifty-five million, five hundred five thousand, five hundred twenty-five".