1320761639 has 2 divisors, whose sum is σ = 1320761640. Its totient is φ = 1320761638.

The previous prime is 1320761623. The next prime is 1320761647. The reversal of 1320761639 is 9361670231.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1320761639 - 2⁴ = 1320761623 is a prime.

It is a super-2 number, since 2×1320761639² = 3488822614107932642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1320764639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660380819 + 660380820.

It is an arithmetic number, because the mean of its divisors is an integer number (660380820).

Almost surely, 2^1320761639 is an apocalyptic number.

1320761639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320761639 is an equidigital number, since it uses as much as digits as its factorization.

1320761639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 38.

The square root of 1320761639 is about 36342.2844493849. The cubic root of 1320761639 is about 1097.1722518691.

The spelling of 1320761639 in words is "one billion, three hundred twenty million, seven hundred sixty-one thousand, six hundred thirty-nine".