7787646491 has 2 divisors, whose sum is σ = 7787646492. Its totient is φ = 7787646490.

The previous prime is 7787646469. The next prime is 7787646499. The reversal of 7787646491 is 1946467877.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7787646491 - 2¹⁸ = 7787384347 is a prime.

It is a super-2 number, since 2×7787646491² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 7787646491.

It is not a weakly prime, because it can be changed into another prime (7787646499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3893823245 + 3893823246.

It is an arithmetic number, because the mean of its divisors is an integer number (3893823246).

Almost surely, 2^7787646491 is an apocalyptic number.

7787646491 is a deficient number, since it is larger than the sum of its proper divisors (1).

7787646491 is an equidigital number, since it uses as much as digits as its factorization.

7787646491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14224896, while the sum is 59.

The square root of 7787646491 is about 88247.6429770223. The cubic root of 7787646491 is about 1982.1449471474.

The spelling of 7787646491 in words is "seven billion, seven hundred eighty-seven million, six hundred forty-six thousand, four hundred ninety-one".