856929747025 has 27 divisors (see below), whose sum is σ = 1168043397339. Its totient is φ = 623184606000.

The previous prime is 856929747019. The next prime is 856929747073. The reversal of 856929747025 is 520747929658.

The square root of 856929747025 is 925705.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 308494708929 + 548435038096 = 555423^2 + 740564^2 .

It is not a de Polignac number, because 856929747025 - 2²⁹ = 856392876113 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 50905360 + ... + 50922190.

Almost surely, 2^856929747025 is an apocalyptic number.

856929747025 is the 925705-th square number.

856929747025 is the 462853-rd centered octagonal number.

It is an amenable number.

856929747025 is a deficient number, since it is larger than the sum of its proper divisors (311113650314).

856929747025 is an frugal number, since it uses more digits than its factorization.

856929747025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33694 (or 16847 counting only the distinct ones).

The product of its (nonzero) digits is 76204800, while the sum is 64.

Multiplying 856929747025 by its sum of digits (64), we get a square (54843503809600 = 7405640²).

The spelling of 856929747025 in words is "eight hundred fifty-six billion, nine hundred twenty-nine million, seven hundred forty-seven thousand, twenty-five".