189722391 has 8 divisors (see below), whose sum is σ = 266277120. Its totient is φ = 119824632.

The previous prime is 189722389. The next prime is 189722399. The reversal of 189722391 is 193227981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 189722391 - 2¹ = 189722389 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189722399) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1664175 + ... + 1664288.

It is an arithmetic number, because the mean of its divisors is an integer number (33284640).

Almost surely, 2^189722391 is an apocalyptic number.

189722391 is a deficient number, since it is larger than the sum of its proper divisors (76554729).

189722391 is a wasteful number, since it uses less digits than its factorization.

189722391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3328485.

The product of its digits is 54432, while the sum is 42.

The square root of 189722391 is about 13773.9751342886. The cubic root of 189722391 is about 574.6095809683.

The spelling of 189722391 in words is "one hundred eighty-nine million, seven hundred twenty-two thousand, three hundred ninety-one".