2640290 has 8 divisors (see below), whose sum is σ = 4752540. Its totient is φ = 1056112.

The previous prime is 2640289. The next prime is 2640299. The reversal of 2640290 is 920462.

It can be written as a sum of positive squares in 2 ways, for example, as 2307361 + 332929 = 1519^2 + 577^2 .

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

It is a super-2 number, since 2×2640290² = 13942262568200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2640299) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132005 + ... + 132024.

2^2640290 is an apocalyptic number.

2640290 is a deficient number, since it is larger than the sum of its proper divisors (2112250).

2640290 is a wasteful number, since it uses less digits than its factorization.

2640290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264036.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 2640290 is about 1624.8969198075. The cubic root of 2640290 is about 138.2135250784.

The spelling of 2640290 in words is "two million, six hundred forty thousand, two hundred ninety".