7818980639 has 2 divisors, whose sum is σ = 7818980640. Its totient is φ = 7818980638.

The previous prime is 7818980597. The next prime is 7818980641. The reversal of 7818980639 is 9360898187.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7818980639 - 2²⁰ = 7817932063 is a prime.

It is a super-2 number, since 2×7818980639² (a number of 21 digits) contains 22 as substring.

Together with 7818980641, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7818983639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3909490319 + 3909490320.

It is an arithmetic number, because the mean of its divisors is an integer number (3909490320).

Almost surely, 2^7818980639 is an apocalyptic number.

7818980639 is a deficient number, since it is larger than the sum of its proper divisors (1).

7818980639 is an equidigital number, since it uses as much as digits as its factorization.

7818980639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5225472, while the sum is 59.

The square root of 7818980639 is about 88425.0000791631. Note that the first 4 decimals coincide. The cubic root of 7818980639 is about 1984.7998232239.

The spelling of 7818980639 in words is "seven billion, eight hundred eighteen million, nine hundred eighty thousand, six hundred thirty-nine".