188493491 has 2 divisors, whose sum is σ = 188493492. Its totient is φ = 188493490.

The previous prime is 188493469. The next prime is 188493499. The reversal of 188493491 is 194394881.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 188493491 - 2²² = 184299187 is a prime.

It is a super-2 number, since 2×188493491² = 71059592298734162, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (188493499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94246745 + 94246746.

It is an arithmetic number, because the mean of its divisors is an integer number (94246746).

Almost surely, 2^188493491 is an apocalyptic number.

188493491 is a deficient number, since it is larger than the sum of its proper divisors (1).

188493491 is an equidigital number, since it uses as much as digits as its factorization.

188493491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 47.

The square root of 188493491 is about 13729.2931719007. The cubic root of 188493491 is about 573.3662417638.

The spelling of 188493491 in words is "one hundred eighty-eight million, four hundred ninety-three thousand, four hundred ninety-one".