7777428641 has 2 divisors, whose sum is σ = 7777428642. Its totient is φ = 7777428640.

The previous prime is 7777428629. The next prime is 7777428647. The reversal of 7777428641 is 1468247777.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7725531025 + 51897616 = 87895^2 + 7204^2 .

It is an emirp because it is prime and its reverse (1468247777) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7777428641 is a prime.

It is not a weakly prime, because it can be changed into another prime (7777428647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3888714320 + 3888714321.

It is an arithmetic number, because the mean of its divisors is an integer number (3888714321).

Almost surely, 2^7777428641 is an apocalyptic number.

It is an amenable number.

7777428641 is a deficient number, since it is larger than the sum of its proper divisors (1).

7777428641 is an equidigital number, since it uses as much as digits as its factorization.

7777428641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3687936, while the sum is 53.

The square root of 7777428641 is about 88189.7309271323. The cubic root of 7777428641 is about 1981.2776708333.

The spelling of 7777428641 in words is "seven billion, seven hundred seventy-seven million, four hundred twenty-eight thousand, six hundred forty-one".