2640621679 has 16 divisors (see below), whose sum is σ = 2822584320. Its totient is φ = 2461726080.

The previous prime is 2640621647. The next prime is 2640621721. The reversal of 2640621679 is 9761260462.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2640621679 - 2⁵ = 2640621647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2640621079) 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 in 15 ways as a sum of consecutive naturals, for example, 915762 + ... + 918640.

It is an arithmetic number, because the mean of its divisors is an integer number (176411520).

Almost surely, 2^2640621679 is an apocalyptic number.

2640621679 is a deficient number, since it is larger than the sum of its proper divisors (181962641).

2640621679 is a wasteful number, since it uses less digits than its factorization.

2640621679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3390.

The product of its (nonzero) digits is 217728, while the sum is 43.

The square root of 2640621679 is about 51386.9796641134. The cubic root of 2640621679 is about 1382.1931239777.

The spelling of 2640621679 in words is "two billion, six hundred forty million, six hundred twenty-one thousand, six hundred seventy-nine".