2640266665 has 8 divisors (see below), whose sum is σ = 3187758528. Its totient is φ = 2099254320.

The previous prime is 2640266659. The next prime is 2640266687. The reversal of 2640266665 is 5666620462.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2640266665 - 2⁷ = 2640266537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1618981 + ... + 1620610.

It is an arithmetic number, because the mean of its divisors is an integer number (398469816).

Almost surely, 2^2640266665 is an apocalyptic number.

It is an amenable number.

2640266665 is a deficient number, since it is larger than the sum of its proper divisors (547491863).

2640266665 is a wasteful number, since it uses less digits than its factorization.

2640266665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3239759.

The product of its (nonzero) digits is 622080, while the sum is 43.

The square root of 2640266665 is about 51383.5252293962. The cubic root of 2640266665 is about 1382.1311789812.

The spelling of 2640266665 in words is "two billion, six hundred forty million, two hundred sixty-six thousand, six hundred sixty-five".