21812429520639 has 24 divisors (see below), whose sum is σ = 32687214402960. Its totient is φ = 13999722834048.

The previous prime is 21812429520601. The next prime is 21812429520643. The reversal of 21812429520639 is 93602592421812.

21812429520639 is a `hidden beast` number, since 2 + 1 + 8 + 1 + 2 + 429 + 5 + 206 + 3 + 9 = 666.

It is not a de Polignac number, because 21812429520639 - 2¹¹ = 21812429518591 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21812429520139) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 120330942 + ... + 120512075.

It is an arithmetic number, because the mean of its divisors is an integer number (1361967266790).

Almost surely, 2^{21812429520639} is an apocalyptic number.

21812429520639 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21812429520639 is a deficient number, since it is larger than the sum of its proper divisors (10874784882321).

21812429520639 is a wasteful number, since it uses less digits than its factorization.

21812429520639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240843399 (or 240843396 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 54.

The spelling of 21812429520639 in words is "twenty-one trillion, eight hundred twelve billion, four hundred twenty-nine million, five hundred twenty thousand, six hundred thirty-nine".