21300681655 has 32 divisors (see below), whose sum is σ = 28181260800. Its totient is φ = 15327377280.

The previous prime is 21300681643. The next prime is 21300681659. The reversal of 21300681655 is 55618600312.

It is not a de Polignac number, because 21300681655 - 2⁷ = 21300681527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21300681659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2150344 + ... + 2160226.

It is an arithmetic number, because the mean of its divisors is an integer number (880664400).

Almost surely, 2^21300681655 is an apocalyptic number.

21300681655 is a deficient number, since it is larger than the sum of its proper divisors (6880579145).

21300681655 is a wasteful number, since it uses less digits than its factorization.

21300681655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10311.

The product of its (nonzero) digits is 43200, while the sum is 37.

The spelling of 21300681655 in words is "twenty-one billion, three hundred million, six hundred eighty-one thousand, six hundred fifty-five".