21138757808315 has 32 divisors (see below), whose sum is σ = 29286138746880. Its totient is φ = 14347910304000.

The previous prime is 21138757808269. The next prime is 21138757808353. The reversal of 21138757808315 is 51380875783112.

It is a happy number.

21138757808315 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 21138757808315 - 2³⁴ = 21121577939131 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5631935 + ... + 8602104.

It is an arithmetic number, because the mean of its divisors is an integer number (915191835840).

Almost surely, 2^{21138757808315} is an apocalyptic number.

21138757808315 is a deficient number, since it is larger than the sum of its proper divisors (8147380938565).

21138757808315 is a wasteful number, since it uses less digits than its factorization.

21138757808315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14234483.

The product of its (nonzero) digits is 11289600, while the sum is 59.

The spelling of 21138757808315 in words is "twenty-one trillion, one hundred thirty-eight billion, seven hundred fifty-seven million, eight hundred eight thousand, three hundred fifteen".