21375413955 has 24 divisors (see below), whose sum is σ = 42343677792. Its totient is φ = 9771617664.

The previous prime is 21375413923. The next prime is 21375413957. The reversal of 21375413955 is 55931457312.

21375413955 is a `hidden beast` number, since 2 + 13 + 7 + 541 + 3 + 95 + 5 = 666.

It is not a de Polignac number, because 21375413955 - 2⁵ = 21375413923 is a prime.

It is a super-4 number, since 4×21375413955⁴ (a number of 42 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 21375413955.

It is not an unprimeable number, because it can be changed into a prime (21375413957) 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 23 ways as a sum of consecutive naturals, for example, 33928914 + ... + 33929543.

It is an arithmetic number, because the mean of its divisors is an integer number (1764319908).

Almost surely, 2^21375413955 is an apocalyptic number.

21375413955 is a deficient number, since it is larger than the sum of its proper divisors (20968263837).

21375413955 is a wasteful number, since it uses less digits than its factorization.

21375413955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67858475 (or 67858472 counting only the distinct ones).

The product of its digits is 567000, while the sum is 45.

The spelling of 21375413955 in words is "twenty-one billion, three hundred seventy-five million, four hundred thirteen thousand, nine hundred fifty-five".