188360021 has 2 divisors, whose sum is σ = 188360022. Its totient is φ = 188360020.

The previous prime is 188359979. The next prime is 188360023. The reversal of 188360021 is 120063881.

188360021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 188073796 + 286225 = 13714^2 + 535^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-188360021 is a prime.

It is a super-2 number, since 2×188360021² = 70958995022240882, which contains 22 as substring.

Together with 188360023, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_10469414 and since 188360021 and 10469414 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (188360023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94180010 + 94180011.

It is an arithmetic number, because the mean of its divisors is an integer number (94180011).

Almost surely, 2^188360021 is an apocalyptic number.

It is an amenable number.

188360021 is a deficient number, since it is larger than the sum of its proper divisors (1).

188360021 is an equidigital number, since it uses as much as digits as its factorization.

188360021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 188360021 is about 13724.4315364972. The cubic root of 188360021 is about 573.2308785360.

The spelling of 188360021 in words is "one hundred eighty-eight million, three hundred sixty thousand, twenty-one".