21511204214751 has 32 divisors (see below), whose sum is σ = 32074038662400. Its totient is φ = 14248519820640.

The previous prime is 21511204214743. The next prime is 21511204214767. The reversal of 21511204214751 is 15741240211512.

21511204214751 is a `hidden beast` number, since 2 + 1 + 511 + 20 + 42 + 14 + 75 + 1 = 666.

It is not a de Polignac number, because 21511204214751 - 2³ = 21511204214743 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21511214214751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 127885 + ... + 6560393.

It is an arithmetic number, because the mean of its divisors is an integer number (1002313708200).

Almost surely, 2^{21511204214751} is an apocalyptic number.

21511204214751 is a deficient number, since it is larger than the sum of its proper divisors (10562834447649).

21511204214751 is a wasteful number, since it uses less digits than its factorization.

21511204214751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6433316 (or 6433310 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 36.

The spelling of 21511204214751 in words is "twenty-one trillion, five hundred eleven billion, two hundred four million, two hundred fourteen thousand, seven hundred fifty-one".