125661338055 has 72 divisors (see below), whose sum is σ = 253497653136. Its totient is φ = 57342743040.

The previous prime is 125661338041. The next prime is 125661338113. The reversal of 125661338055 is 550833166521.

125661338055 is a `hidden beast` number, since 1 + 2 + 566 + 1 + 3 + 3 + 80 + 5 + 5 = 666.

It is not a de Polignac number, because 125661338055 - 2⁴ = 125661338039 is a prime.

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

It is a self number, because there is not a number n which added to its sum of digits gives 125661338055.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 586209 + ... + 771338.

It is an arithmetic number, because the mean of its divisors is an integer number (3520800738).

Almost surely, 2^125661338055 is an apocalyptic number.

125661338055 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

125661338055 is an abundant number, since it is smaller than the sum of its proper divisors (127836315081).

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

125661338055 is a wasteful number, since it uses less digits than its factorization.

125661338055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1357597 (or 1357583 counting only the distinct ones).

The product of its (nonzero) digits is 648000, while the sum is 45.

The spelling of 125661338055 in words is "one hundred twenty-five billion, six hundred sixty-one million, three hundred thirty-eight thousand, fifty-five".