125221665 has 32 divisors (see below), whose sum is σ = 204906240. Its totient is φ = 65286144.

The previous prime is 125221661. The next prime is 125221687. The reversal of 125221665 is 566122521.

It is not a de Polignac number, because 125221665 - 2² = 125221661 is a prime.

It is not an unprimeable number, because it can be changed into a prime (125221661) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129012 + ... + 129978.

It is an arithmetic number, because the mean of its divisors is an integer number (6403320).

Almost surely, 2^125221665 is an apocalyptic number.

125221665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

125221665 is a deficient number, since it is larger than the sum of its proper divisors (79684575).

125221665 is an equidigital number, since it uses as much as digits as its factorization.

125221665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1161.

The product of its digits is 7200, while the sum is 30.

The square root of 125221665 is about 11190.2486567547. The cubic root of 125221665 is about 500.2953788017.

The spelling of 125221665 in words is "one hundred twenty-five million, two hundred twenty-one thousand, six hundred sixty-five".