851621000520 has 64 divisors (see below), whose sum is σ = 2554930768320. Its totient is φ = 227092909824.

The previous prime is 851621000501. The next prime is 851621000551. The reversal of 851621000520 is 25000126158.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6189594 + ... + 6325686.

It is an arithmetic number, because the mean of its divisors is an integer number (39920793255).

Almost surely, 2^851621000520 is an apocalyptic number.

It is an amenable number.

851621000520 is an abundant number, since it is smaller than the sum of its proper divisors (1703309767800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

851621000520 is a wasteful number, since it uses less digits than its factorization.

851621000520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188254 (or 188250 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 30.

Adding to 851621000520 its reverse (25000126158), we get a palindrome (876621126678).

The spelling of 851621000520 in words is "eight hundred fifty-one billion, six hundred twenty-one million, five hundred twenty", and thus it is an aban number.