16391139 has 4 divisors (see below), whose sum is σ = 21854856. Its totient is φ = 10927424.

The previous prime is 16391107. The next prime is 16391143. The reversal of 16391139 is 93119361.

It is a happy number.

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 16391139 - 2⁵ = 16391107 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16391159) 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, 2731854 + ... + 2731859.

It is an arithmetic number, because the mean of its divisors is an integer number (5463714).

Almost surely, 2^16391139 is an apocalyptic number.

16391139 is a deficient number, since it is larger than the sum of its proper divisors (5463717).

16391139 is an equidigital number, since it uses as much as digits as its factorization.

16391139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5463716.

The product of its digits is 4374, while the sum is 33.

The square root of 16391139 is about 4048.5971644509. The cubic root of 16391139 is about 254.0210524638.

The spelling of 16391139 in words is "sixteen million, three hundred ninety-one thousand, one hundred thirty-nine".