188798993 has 4 divisors (see below), whose sum is σ = 190920420. Its totient is φ = 186677568.

The previous prime is 188798989. The next prime is 188798999. The reversal of 188798993 is 399897881.

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 92602129 + 96196864 = 9623^2 + 9808^2 .

It is a cyclic number.

It is not a de Polignac number, because 188798993 - 2² = 188798989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (188798999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1060580 + ... + 1060757.

It is an arithmetic number, because the mean of its divisors is an integer number (47730105).

Almost surely, 2^188798993 is an apocalyptic number.

It is an amenable number.

188798993 is a deficient number, since it is larger than the sum of its proper divisors (2121427).

188798993 is an equidigital number, since it uses as much as digits as its factorization.

188798993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2121426.

The product of its digits is 7838208, while the sum is 62.

The square root of 188798993 is about 13740.4145861761. The cubic root of 188798993 is about 573.6758368675.

It can be divided in two parts, 18879 and 8993, that added together give a palindrome (27872).

The spelling of 188798993 in words is "one hundred eighty-eight million, seven hundred ninety-eight thousand, nine hundred ninety-three".