125621852778 has 128 divisors (see below), whose sum is σ = 306938419200. Its totient is φ = 37906932096.

The previous prime is 125621852777. The next prime is 125621852819. The reversal of 125621852778 is 877258126521.

It is a happy number.

125621852778 is a `hidden beast` number, since 1 + 2 + 5 + 621 + 8 + 5 + 2 + 7 + 7 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (125621852773) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 30840550 + ... + 30844622.

It is an arithmetic number, because the mean of its divisors is an integer number (2397956400).

Almost surely, 2^125621852778 is an apocalyptic number.

125621852778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 125621852778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153469209600).

125621852778 is an abundant number, since it is smaller than the sum of its proper divisors (181316566422).

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

125621852778 is a wasteful number, since it uses less digits than its factorization.

125621852778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5433 (or 5427 counting only the distinct ones).

The product of its digits is 3763200, while the sum is 54.

The spelling of 125621852778 in words is "one hundred twenty-five billion, six hundred twenty-one million, eight hundred fifty-two thousand, seven hundred seventy-eight".