991672319 has 6 divisors (see below), whose sum is σ = 1090020120. Its totient is φ = 901520180.

The previous prime is 991672309. The next prime is 991672387. The reversal of 991672319 is 913276199.

It is not a de Polignac number, because 991672319 - 2¹⁶ = 991606783 is a prime.

It is a super-2 number, since 2×991672319² = 1966827976541675522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991672309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4097699 + ... + 4097940.

It is an arithmetic number, because the mean of its divisors is an integer number (181670020).

Almost surely, 2^991672319 is an apocalyptic number.

991672319 is a deficient number, since it is larger than the sum of its proper divisors (98347801).

991672319 is a wasteful number, since it uses less digits than its factorization.

991672319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8195661 (or 8195650 counting only the distinct ones).

The product of its digits is 183708, while the sum is 47.

The square root of 991672319 is about 31490.8291253184. The cubic root of 991672319 is about 997.2163648987.

The spelling of 991672319 in words is "nine hundred ninety-one million, six hundred seventy-two thousand, three hundred nineteen".