188378625981 has 64 divisors (see below), whose sum is σ = 321169605120. Its totient is φ = 95525498880.

The previous prime is 188378625973. The next prime is 188378625983. The reversal of 188378625981 is 189526873881.

It is not a de Polignac number, because 188378625981 - 2³ = 188378625973 is a prime.

It is a super-2 number, since 2×188378625981² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (188378625983) 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, 1793601 + ... + 1895721.

It is an arithmetic number, because the mean of its divisors is an integer number (5018275080).

Almost surely, 2^188378625981 is an apocalyptic number.

It is an amenable number.

188378625981 is a deficient number, since it is larger than the sum of its proper divisors (132790979139).

188378625981 is a wasteful number, since it uses less digits than its factorization.

188378625981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102406.

The product of its digits is 46448640, while the sum is 66.

The spelling of 188378625981 in words is "one hundred eighty-eight billion, three hundred seventy-eight million, six hundred twenty-five thousand, nine hundred eighty-one".