309570139 has 2 divisors, whose sum is σ = 309570140. Its totient is φ = 309570138.

The previous prime is 309570077. The next prime is 309570143. The reversal of 309570139 is 931075903.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-309570139 is a prime.

It is equal to p_16742548 and since 309570139 and 16742548 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 309570098 and 309570107.

It is not a weakly prime, because it can be changed into another prime (309570169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154785069 + 154785070.

It is an arithmetic number, because the mean of its divisors is an integer number (154785070).

Almost surely, 2^309570139 is an apocalyptic number.

309570139 is a deficient number, since it is larger than the sum of its proper divisors (1).

309570139 is an equidigital number, since it uses as much as digits as its factorization.

309570139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25515, while the sum is 37.

The square root of 309570139 is about 17594.6053948362. The cubic root of 309570139 is about 676.4769772786.

The spelling of 309570139 in words is "three hundred nine million, five hundred seventy thousand, one hundred thirty-nine".