189690993 has 12 divisors (see below), whose sum is σ = 274330420. Its totient is φ = 126307296.

The previous prime is 189690989. The next prime is 189690997. The reversal of 189690993 is 399096981.

It is an interprime number because it is at equal distance from previous prime (189690989) and next prime (189690997).

It can be written as a sum of positive squares in 2 ways, for example, as 61027344 + 128663649 = 7812^2 + 11343^2 .

It is not a de Polignac number, because 189690993 - 2² = 189690989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189690997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4678 + ... + 20031.

Almost surely, 2^189690993 is an apocalyptic number.

It is an amenable number.

189690993 is a deficient number, since it is larger than the sum of its proper divisors (84639427).

189690993 is a wasteful number, since it uses less digits than its factorization.

189690993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25568 (or 25565 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 54.

The square root of 189690993 is about 13772.8353290091. The cubic root of 189690993 is about 574.5778809901.

The spelling of 189690993 in words is "one hundred eighty-nine million, six hundred ninety thousand, nine hundred ninety-three".