189809493 has 4 divisors (see below), whose sum is σ = 253079328. Its totient is φ = 126539660.

The previous prime is 189809479. The next prime is 189809509. The reversal of 189809493 is 394908981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 394908981 = 3 ⋅131636327.

It is a cyclic number.

It is not a de Polignac number, because 189809493 - 2⁸ = 189809237 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189809443) 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, 31634913 + ... + 31634918.

It is an arithmetic number, because the mean of its divisors is an integer number (63269832).

Almost surely, 2^189809493 is an apocalyptic number.

It is an amenable number.

189809493 is a deficient number, since it is larger than the sum of its proper divisors (63269835).

189809493 is an equidigital number, since it uses as much as digits as its factorization.

189809493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63269834.

The product of its (nonzero) digits is 559872, while the sum is 51.

The square root of 189809493 is about 13777.1366038085. The cubic root of 189809493 is about 574.6975023888.

The spelling of 189809493 in words is "one hundred eighty-nine million, eight hundred nine thousand, four hundred ninety-three".