2640640477 has 2 divisors, whose sum is σ = 2640640478. Its totient is φ = 2640640476.

The previous prime is 2640640469. The next prime is 2640640487. The reversal of 2640640477 is 7740460462.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2320445241 + 320195236 = 48171^2 + 17894^2 .

It is a cyclic number.

It is not a de Polignac number, because 2640640477 - 2³ = 2640640469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2640640417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1320320238 + 1320320239.

It is an arithmetic number, because the mean of its divisors is an integer number (1320320239).

Almost surely, 2^2640640477 is an apocalyptic number.

It is an amenable number.

2640640477 is a deficient number, since it is larger than the sum of its proper divisors (1).

2640640477 is an equidigital number, since it uses as much as digits as its factorization.

2640640477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 225792, while the sum is 40.

The square root of 2640640477 is about 51387.1625700427. The cubic root of 2640640477 is about 1382.1964038120.

The spelling of 2640640477 in words is "two billion, six hundred forty million, six hundred forty thousand, four hundred seventy-seven".