189720319 has 4 divisors (see below), whose sum is σ = 191598840. Its totient is φ = 187841800.

The previous prime is 189720313. The next prime is 189720329. The reversal of 189720319 is 913027981.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 189720319 - 2⁵ = 189720287 is a prime.

It is a super-2 number, since 2×189720319² = 71987598882923522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189720313) 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, 939109 + ... + 939310.

It is an arithmetic number, because the mean of its divisors is an integer number (47899710).

Almost surely, 2^189720319 is an apocalyptic number.

189720319 is a deficient number, since it is larger than the sum of its proper divisors (1878521).

189720319 is a wasteful number, since it uses less digits than its factorization.

189720319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1878520.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 189720319 is about 13773.8999197758. The cubic root of 189720319 is about 574.6074891481.

The spelling of 189720319 in words is "one hundred eighty-nine million, seven hundred twenty thousand, three hundred nineteen".