15779880 has 128 divisors (see below), whose sum is σ = 55440000. Its totient is φ = 3981312.

The previous prime is 15779879. The next prime is 15779891. The reversal of 15779880 is 8897751.

It is a super-2 number, since 2×15779880² = 498009225628800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20136 + ... + 20904.

It is an arithmetic number, because the mean of its divisors is an integer number (433125).

Almost surely, 2^15779880 is an apocalyptic number.

15779880 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 15779880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27720000).

15779880 is an abundant number, since it is smaller than the sum of its proper divisors (39660120).

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

15779880 is a wasteful number, since it uses less digits than its factorization.

15779880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808 (or 798 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The square root of 15779880 is about 3972.3897089787. The cubic root of 15779880 is about 250.8233123176.

The spelling of 15779880 in words is "fifteen million, seven hundred seventy-nine thousand, eight hundred eighty".