139566971 has 2 divisors, whose sum is σ = 139566972. Its totient is φ = 139566970.

The previous prime is 139566961. The next prime is 139566983. The reversal of 139566971 is 179665931.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139566971 is a prime.

It is a super-2 number, since 2×139566971² = 38957878788229682, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (139566941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69783485 + 69783486.

It is an arithmetic number, because the mean of its divisors is an integer number (69783486).

Almost surely, 2^139566971 is an apocalyptic number.

139566971 is a deficient number, since it is larger than the sum of its proper divisors (1).

139566971 is an equidigital number, since it uses as much as digits as its factorization.

139566971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 306180, while the sum is 47.

The square root of 139566971 is about 11813.8465793322. The cubic root of 139566971 is about 518.7135000012.

The spelling of 139566971 in words is "one hundred thirty-nine million, five hundred sixty-six thousand, nine hundred seventy-one".