189915949 has 2 divisors, whose sum is σ = 189915950. Its totient is φ = 189915948.

The previous prime is 189915937. The next prime is 189916007. The reversal of 189915949 is 949519981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107433225 + 82482724 = 10365^2 + 9082^2 .

It is a cyclic number.

It is not a de Polignac number, because 189915949 - 2⁵ = 189915917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 189915949.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (189910949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94957974 + 94957975.

It is an arithmetic number, because the mean of its divisors is an integer number (94957975).

Almost surely, 2^189915949 is an apocalyptic number.

It is an amenable number.

189915949 is a deficient number, since it is larger than the sum of its proper divisors (1).

189915949 is an equidigital number, since it uses as much as digits as its factorization.

189915949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1049760, while the sum is 55.

The square root of 189915949 is about 13780.9995646179. Note that the first 3 decimals coincide. The cubic root of 189915949 is about 574.8049233651.

The spelling of 189915949 in words is "one hundred eighty-nine million, nine hundred fifteen thousand, nine hundred forty-nine".