15965921380 has 24 divisors (see below), whose sum is σ = 33678796032. Its totient is φ = 6357728352.

The previous prime is 15965921357. The next prime is 15965921381. The reversal of 15965921380 is 8312956951.

It is a super-2 number, since 2×15965921380² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (15965921381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1785442 + ... + 1794361.

It is an arithmetic number, because the mean of its divisors is an integer number (1403283168).

Almost surely, 2^15965921380 is an apocalyptic number.

15965921380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15965921380 is an abundant number, since it is smaller than the sum of its proper divisors (17712874652).

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

15965921380 is a wasteful number, since it uses less digits than its factorization.

15965921380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3580035 (or 3580033 counting only the distinct ones).

The product of its (nonzero) digits is 583200, while the sum is 49.

The spelling of 15965921380 in words is "fifteen billion, nine hundred sixty-five million, nine hundred twenty-one thousand, three hundred eighty".