188620301981 has 2 divisors, whose sum is σ = 188620301982. Its totient is φ = 188620301980.

The previous prime is 188620301959. The next prime is 188620302089. The reversal of 188620301981 is 189103026881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 100003942756 + 88616359225 = 316234^2 + 297685^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-188620301981 is a prime.

It is a super-3 number, since 3×188620301981³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (188620301081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94310150990 + 94310150991.

It is an arithmetic number, because the mean of its divisors is an integer number (94310150991).

Almost surely, 2^188620301981 is an apocalyptic number.

It is an amenable number.

188620301981 is a deficient number, since it is larger than the sum of its proper divisors (1).

188620301981 is an equidigital number, since it uses as much as digits as its factorization.

188620301981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 165888, while the sum is 47.

The spelling of 188620301981 in words is "one hundred eighty-eight billion, six hundred twenty million, three hundred one thousand, nine hundred eighty-one".