1390656739 has 2 divisors, whose sum is σ = 1390656740. Its totient is φ = 1390656738.

The previous prime is 1390656733. The next prime is 1390656769. The reversal of 1390656739 is 9376560931.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1390656739 - 2¹³ = 1390648547 is a prime.

It is a super-2 number, since 2×1390656739² = 3867852331452228242, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1390656692 and 1390656701.

It is not a weakly prime, because it can be changed into another prime (1390656733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695328369 + 695328370.

It is an arithmetic number, because the mean of its divisors is an integer number (695328370).

Almost surely, 2^1390656739 is an apocalyptic number.

1390656739 is a deficient number, since it is larger than the sum of its proper divisors (1).

1390656739 is an equidigital number, since it uses as much as digits as its factorization.

1390656739 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 918540, while the sum is 49.

The square root of 1390656739 is about 37291.5102804915. The cubic root of 1390656739 is about 1116.1947656095.

The spelling of 1390656739 in words is "one billion, three hundred ninety million, six hundred fifty-six thousand, seven hundred thirty-nine".