21275156155 has 16 divisors (see below), whose sum is σ = 27882933984. Its totient is φ = 15455162880.

The previous prime is 21275156143. The next prime is 21275156183. The reversal of 21275156155 is 55165157212.

It is a de Polignac number, because none of the positive numbers 2^k-21275156155 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 172302 + ... + 268771.

It is an arithmetic number, because the mean of its divisors is an integer number (1742683374).

Almost surely, 2^21275156155 is an apocalyptic number.

21275156155 is a deficient number, since it is larger than the sum of its proper divisors (6607777829).

21275156155 is a wasteful number, since it uses less digits than its factorization.

21275156155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441966.

The product of its digits is 105000, while the sum is 40.

The spelling of 21275156155 in words is "twenty-one billion, two hundred seventy-five million, one hundred fifty-six thousand, one hundred fifty-five".