856829701981 has 32 divisors (see below), whose sum is σ = 963056174976. Its totient is φ = 755464320000.

The previous prime is 856829701979. The next prime is 856829701991. The reversal of 856829701981 is 189107928658.

It is a cyclic number.

It is not a de Polignac number, because 856829701981 - 2¹ = 856829701979 is a prime.

It is a super-2 number, since 2×856829701981² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856829701991) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 186143626 + ... + 186148228.

It is an arithmetic number, because the mean of its divisors is an integer number (30095505468).

Almost surely, 2^856829701981 is an apocalyptic number.

It is an amenable number.

856829701981 is a deficient number, since it is larger than the sum of its proper divisors (106226472995).

856829701981 is a wasteful number, since it uses less digits than its factorization.

856829701981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6013.

The product of its (nonzero) digits is 17418240, while the sum is 64.

The spelling of 856829701981 in words is "eight hundred fifty-six billion, eight hundred twenty-nine million, seven hundred one thousand, nine hundred eighty-one".