125636661 has 6 divisors (see below), whose sum is σ = 181475190. Its totient is φ = 83757768.

The previous prime is 125636657. The next prime is 125636663. The reversal of 125636661 is 166636521.

It can be written as a sum of positive squares in only one way, i.e., 124211025 + 1425636 = 11145^2 + 1194^2 .

It is not a de Polignac number, because 125636661 - 2² = 125636657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125636663) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6979806 + ... + 6979823.

It is an arithmetic number, because the mean of its divisors is an integer number (30245865).

Almost surely, 2^125636661 is an apocalyptic number.

It is an amenable number.

125636661 is a deficient number, since it is larger than the sum of its proper divisors (55838529).

125636661 is a wasteful number, since it uses less digits than its factorization.

125636661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13959635 (or 13959632 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The square root of 125636661 is about 11208.7760705619. The cubic root of 125636661 is about 500.8474441985.

The spelling of 125636661 in words is "one hundred twenty-five million, six hundred thirty-six thousand, six hundred sixty-one".