21592539137 has 16 divisors (see below), whose sum is σ = 24632249040. Its totient is φ = 18750830592.

The previous prime is 21592539109. The next prime is 21592539161. The reversal of 21592539137 is 73193529512.

It is a Cunningham number, because it is equal to 146944²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 1 + 21592539136 = 1^2 + 146944^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21592539137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21592539091 and 21592539100.

It is not an unprimeable number, because it can be changed into a prime (21592539737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 508439 + ... + 549267.

It is an arithmetic number, because the mean of its divisors is an integer number (1539515565).

It is a Proth number, since it is equal to 82369 ⋅ 2¹⁸ + 1 and 82369 < 2¹⁸.

Almost surely, 2^21592539137 is an apocalyptic number.

It is an amenable number.

21592539137 is a deficient number, since it is larger than the sum of its proper divisors (3039709903).

21592539137 is a wasteful number, since it uses less digits than its factorization.

21592539137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43252.

The product of its digits is 510300, while the sum is 47.

The spelling of 21592539137 in words is "twenty-one billion, five hundred ninety-two million, five hundred thirty-nine thousand, one hundred thirty-seven".