21520426754775 has 192 divisors, whose sum is σ = 41019319040000. Its totient is φ = 9867152401920.

The previous prime is 21520426754767. The next prime is 21520426754777. The reversal of 21520426754775 is 57745762402512.

It is not a de Polignac number, because 21520426754775 - 2³ = 21520426754767 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21520426754777) 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 191 ways as a sum of consecutive naturals, for example, 619328952 + ... + 619363698.

Almost surely, 2^{21520426754775} is an apocalyptic number.

21520426754775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21520426754775 is a deficient number, since it is larger than the sum of its proper divisors (19498892285225).

21520426754775 is a wasteful number, since it uses less digits than its factorization.

21520426754775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35358 (or 35353 counting only the distinct ones).

The product of its (nonzero) digits is 32928000, while the sum is 57.

The spelling of 21520426754775 in words is "twenty-one trillion, five hundred twenty billion, four hundred twenty-six million, seven hundred fifty-four thousand, seven hundred seventy-five".