856721016 has 64 divisors (see below), whose sum is σ = 2461860000. Its totient is φ = 275724288.

The previous prime is 856721009. The next prime is 856721059. The reversal of 856721016 is 610127658.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

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, 62121 + ... + 74648.

Almost surely, 2^856721016 is an apocalyptic number.

It is an amenable number.

856721016 is an abundant number, since it is smaller than the sum of its proper divisors (1605138984).

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

856721016 is a wasteful number, since it uses less digits than its factorization.

856721016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136813 (or 136803 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 856721016 is about 29269.7969928047. The cubic root of 856721016 is about 949.7583932220.

The spelling of 856721016 in words is "eight hundred fifty-six million, seven hundred twenty-one thousand, sixteen".