21311513541 has 12 divisors (see below), whose sum is σ = 31007994732. Its totient is φ = 14103969216.

The previous prime is 21311513527. The next prime is 21311513551. The reversal of 21311513541 is 14531511312.

21311513541 is a `hidden beast` number, since 2 + 1 + 3 + 115 + 1 + 3 + 541 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 18239582916 + 3071930625 = 135054^2 + 55425^2 .

It is not a de Polignac number, because 21311513541 - 2¹⁰ = 21311512517 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311513521) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 8640906 + ... + 8643371.

It is an arithmetic number, because the mean of its divisors is an integer number (2583999561).

Almost surely, 2^21311513541 is an apocalyptic number.

It is an amenable number.

21311513541 is a deficient number, since it is larger than the sum of its proper divisors (9696481191).

21311513541 is a wasteful number, since it uses less digits than its factorization.

21311513541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17284420 (or 17284417 counting only the distinct ones).

The product of its digits is 1800, while the sum is 27.

The spelling of 21311513541 in words is "twenty-one billion, three hundred eleven million, five hundred thirteen thousand, five hundred forty-one".