21156607701 has 8 divisors (see below), whose sum is σ = 31343122560. Its totient is φ = 14104405116.

The previous prime is 21156607679. The next prime is 21156607709. The reversal of 21156607701 is 10770665112.

21156607701 is a `hidden beast` number, since 21 + 1 + 566 + 0 + 7 + 70 + 1 = 666.

It is not a de Polignac number, because 21156607701 - 2⁹ = 21156607189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21156607709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 391789005 + ... + 391789058.

It is an arithmetic number, because the mean of its divisors is an integer number (3917890320).

Almost surely, 2^21156607701 is an apocalyptic number.

It is an amenable number.

21156607701 is a deficient number, since it is larger than the sum of its proper divisors (10186514859).

21156607701 is an equidigital number, since it uses as much as digits as its factorization.

21156607701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783578072 (or 783578066 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 36.

The spelling of 21156607701 in words is "twenty-one billion, one hundred fifty-six million, six hundred seven thousand, seven hundred one".