21931658255 has 16 divisors (see below), whose sum is σ = 28489319040. Its totient is φ = 16111761408.

The previous prime is 21931658237. The next prime is 21931658267. The reversal of 21931658255 is 55285613912.

It is a cyclic number.

It is not a de Polignac number, because 21931658255 - 2¹⁴ = 21931641871 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 861575 + ... + 886664.

It is an arithmetic number, because the mean of its divisors is an integer number (1780582440).

Almost surely, 2^21931658255 is an apocalyptic number.

21931658255 is a deficient number, since it is larger than the sum of its proper divisors (6557660785).

21931658255 is a wasteful number, since it uses less digits than its factorization.

21931658255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1748450.

The product of its digits is 648000, while the sum is 47.

The spelling of 21931658255 in words is "twenty-one billion, nine hundred thirty-one million, six hundred fifty-eight thousand, two hundred fifty-five".