188919901 has 4 divisors (see below), whose sum is σ = 189079452. Its totient is φ = 188760352.

The previous prime is 188919883. The next prime is 188919917. The reversal of 188919901 is 109919881.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 133402500 + 55517401 = 11550^2 + 7451^2 .

It is a cyclic number.

It is not a de Polignac number, because 188919901 - 2¹⁵ = 188887133 is a prime.

It is a super-4 number, since 4×188919901⁴ (a number of 34 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (188916901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77986 + ... + 80371.

It is an arithmetic number, because the mean of its divisors is an integer number (47269863).

Almost surely, 2^188919901 is an apocalyptic number.

It is an amenable number.

188919901 is a deficient number, since it is larger than the sum of its proper divisors (159551).

188919901 is a wasteful number, since it uses less digits than its factorization.

188919901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159550.

The product of its (nonzero) digits is 46656, while the sum is 46.

The square root of 188919901 is about 13744.8136036834. The cubic root of 188919901 is about 573.7982725431.

The spelling of 188919901 in words is "one hundred eighty-eight million, nine hundred nineteen thousand, nine hundred one".