125991720 has 128 divisors (see below), whose sum is σ = 429897600. Its totient is φ = 32804352.

The previous prime is 125991707. The next prime is 125991757. The reversal of 125991720 is 27199521.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45084 + ... + 47796.

It is an arithmetic number, because the mean of its divisors is an integer number (3358575).

Almost surely, 2^125991720 is an apocalyptic number.

125991720 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 125991720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (214948800).

125991720 is an abundant number, since it is smaller than the sum of its proper divisors (303905880).

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

125991720 is a wasteful number, since it uses less digits than its factorization.

125991720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2776 (or 2766 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 36.

The square root of 125991720 is about 11224.6033337486. The cubic root of 125991720 is about 501.3188117461.

The spelling of 125991720 in words is "one hundred twenty-five million, nine hundred ninety-one thousand, seven hundred twenty".