15965921440 has 96 divisors (see below), whose sum is σ = 43366627584. Its totient is φ = 5441187840.

The previous prime is 15965921423. The next prime is 15965921441. The reversal of 15965921440 is 4412956951.

It is not an unprimeable number, because it can be changed into a prime (15965921441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144360 + ... + 229720.

It is an arithmetic number, because the mean of its divisors is an integer number (451735704).

Almost surely, 2^15965921440 is an apocalyptic number.

15965921440 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 15965921440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21683313792).

15965921440 is an abundant number, since it is smaller than the sum of its proper divisors (27400706144).

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

15965921440 is a wasteful number, since it uses less digits than its factorization.

15965921440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85550 (or 85542 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 46.

The spelling of 15965921440 in words is "fifteen billion, nine hundred sixty-five million, nine hundred twenty-one thousand, four hundred forty".