15421688720 has 40 divisors (see below), whose sum is σ = 37964572344. Its totient is φ = 5805811712.

The previous prime is 15421688719. The next prime is 15421688731. The reversal of 15421688720 is 2788612451.

It can be written as a sum of positive squares in 4 ways, for example, as 4735091344 + 10686597376 = 68812^2 + 103376^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5668379 + ... + 5671098.

Almost surely, 2^15421688720 is an apocalyptic number.

15421688720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15421688720 is an abundant number, since it is smaller than the sum of its proper divisors (22542883624).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15421688720 is a wasteful number, since it uses less digits than its factorization.

15421688720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11339507 (or 11339501 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 44.

The spelling of 15421688720 in words is "fifteen billion, four hundred twenty-one million, six hundred eighty-eight thousand, seven hundred twenty".