185215139 has 2 divisors, whose sum is σ = 185215140. Its totient is φ = 185215138.

The previous prime is 185215133. The next prime is 185215157. The reversal of 185215139 is 931512581.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 185215139 - 2¹⁶ = 185149603 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 185215099 and 185215108.

It is not a weakly prime, because it can be changed into another prime (185215133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 92607569 + 92607570.

It is an arithmetic number, because the mean of its divisors is an integer number (92607570).

Almost surely, 2^185215139 is an apocalyptic number.

185215139 is a deficient number, since it is larger than the sum of its proper divisors (1).

185215139 is an equidigital number, since it uses as much as digits as its factorization.

185215139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 35.

The square root of 185215139 is about 13609.3768777266. The cubic root of 185215139 is about 570.0227127504.

The spelling of 185215139 in words is "one hundred eighty-five million, two hundred fifteen thousand, one hundred thirty-nine".