125568721 has 4 divisors (see below), whose sum is σ = 125593600. Its totient is φ = 125543844.

The previous prime is 125568719. The next prime is 125568727. The reversal of 125568721 is 127865521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 125568721 - 2¹ = 125568719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125568727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1881 + ... + 15958.

It is an arithmetic number, because the mean of its divisors is an integer number (31398400).

Almost surely, 2^125568721 is an apocalyptic number.

It is an amenable number.

125568721 is a deficient number, since it is larger than the sum of its proper divisors (24879).

125568721 is an equidigital number, since it uses as much as digits as its factorization.

125568721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24878.

The product of its digits is 33600, while the sum is 37.

The square root of 125568721 is about 11205.7449997758. The cubic root of 125568721 is about 500.7571475431.

The spelling of 125568721 in words is "one hundred twenty-five million, five hundred sixty-eight thousand, seven hundred twenty-one".