21512315100424 has 16 divisors (see below), whose sum is σ = 40335668168400. Its totient is φ = 10756136922192.

The previous prime is 21512315100383. The next prime is 21512315100439. The reversal of 21512315100424 is 42400151321512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2424759 + ... + 6993145.

It is an arithmetic number, because the mean of its divisors is an integer number (2520979260525).

Almost surely, 2^{21512315100424} is an apocalyptic number.

It is an amenable number.

21512315100424 is a deficient number, since it is larger than the sum of its proper divisors (18823353067976).

21512315100424 is a wasteful number, since it uses less digits than its factorization.

21512315100424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5157012 (or 5157008 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

Adding to 21512315100424 its reverse (42400151321512), we get a palindrome (63912466421936).

The spelling of 21512315100424 in words is "twenty-one trillion, five hundred twelve billion, three hundred fifteen million, one hundred thousand, four hundred twenty-four".