15720215940 has 720 divisors, whose sum is σ = 60561177600. Its totient is φ = 3387225600.

The previous prime is 15720215939. The next prime is 15720215969. The reversal of 15720215940 is 4951202751.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 15720215895 and 15720215904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 78995961 + ... + 78996159.

Almost surely, 2^15720215940 is an apocalyptic number.

15720215940 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 15720215940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30280588800).

15720215940 is an abundant number, since it is smaller than the sum of its proper divisors (44840961660).

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

15720215940 is a wasteful number, since it uses less digits than its factorization.

15720215940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286 (or 264 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The spelling of 15720215940 in words is "fifteen billion, seven hundred twenty million, two hundred fifteen thousand, nine hundred forty".