15721467720 has 192 divisors, whose sum is σ = 56635200000. Its totient is φ = 3477519360.

The previous prime is 15721467701. The next prime is 15721467731. The reversal of 15721467720 is 2776412751.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 139156 + ... + 225404.

It is an arithmetic number, because the mean of its divisors is an integer number (294975000).

Almost surely, 2^15721467720 is an apocalyptic number.

15721467720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15721467720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28317600000).

15721467720 is an abundant number, since it is smaller than the sum of its proper divisors (40913732280).

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

15721467720 is a wasteful number, since it uses less digits than its factorization.

15721467720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86308 (or 86297 counting only the distinct ones).

The product of its (nonzero) digits is 164640, while the sum is 42.

The spelling of 15721467720 in words is "fifteen billion, seven hundred twenty-one million, four hundred sixty-seven thousand, seven hundred twenty".