21297506226537 has 16 divisors (see below), whose sum is σ = 28604601829440. Its totient is φ = 14094720024000.

The previous prime is 21297506226509. The next prime is 21297506226551. The reversal of 21297506226537 is 73562260579212.

It is not a de Polignac number, because 21297506226537 - 2²³ = 21297497837929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21297506226937) 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 15 ways as a sum of consecutive naturals, for example, 42999714 + ... + 43492187.

It is an arithmetic number, because the mean of its divisors is an integer number (1787787614340).

Almost surely, 2^{21297506226537} is an apocalyptic number.

It is an amenable number.

21297506226537 is a deficient number, since it is larger than the sum of its proper divisors (7307095602903).

21297506226537 is a wasteful number, since it uses less digits than its factorization.

21297506226537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86492504.

The product of its (nonzero) digits is 19051200, while the sum is 57.

The spelling of 21297506226537 in words is "twenty-one trillion, two hundred ninety-seven billion, five hundred six million, two hundred twenty-six thousand, five hundred thirty-seven".