188899969 has 2 divisors, whose sum is σ = 188899970. Its totient is φ = 188899968.

The previous prime is 188899967. The next prime is 188899987. The reversal of 188899969 is 969998881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 178089025 + 10810944 = 13345^2 + 3288^2 .

It is a cyclic number.

It is not a de Polignac number, because 188899969 - 2¹ = 188899967 is a prime.

It is a super-2 number, since 2×188899969² = 71366396576401922, which contains 22 as substring.

Together with 188899967, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (188899967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94449984 + 94449985.

It is an arithmetic number, because the mean of its divisors is an integer number (94449985).

Almost surely, 2^188899969 is an apocalyptic number.

It is an amenable number.

188899969 is a deficient number, since it is larger than the sum of its proper divisors (1).

188899969 is an equidigital number, since it uses as much as digits as its factorization.

188899969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20155392, while the sum is 67.

The square root of 188899969 is about 13744.0885110654. The cubic root of 188899969 is about 573.7780922985.

The spelling of 188899969 in words is "one hundred eighty-eight million, eight hundred ninety-nine thousand, nine hundred sixty-nine".