188798989 has 2 divisors, whose sum is σ = 188798990. Its totient is φ = 188798988.

The previous prime is 188798983. The next prime is 188798999. The reversal of 188798989 is 989897881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 131675625 + 57123364 = 11475^2 + 7558^2 .

It is a cyclic number.

It is not a de Polignac number, because 188798989 - 2²³ = 180410381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (188798983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94399494 + 94399495.

It is an arithmetic number, because the mean of its divisors is an integer number (94399495).

Almost surely, 2^188798989 is an apocalyptic number.

It is an amenable number.

188798989 is a deficient number, since it is larger than the sum of its proper divisors (1).

188798989 is an equidigital number, since it uses as much as digits as its factorization.

188798989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20901888, while the sum is 67.

The square root of 188798989 is about 13740.4144406200. The cubic root of 188798989 is about 573.6758328161.

The spelling of 188798989 in words is "one hundred eighty-eight million, seven hundred ninety-eight thousand, nine hundred eighty-nine".