6640258426 has 8 divisors (see below), whose sum is σ = 9960757524. Its totient is φ = 3320005920.

The previous prime is 6640258403. The next prime is 6640258439. The reversal of 6640258426 is 6248520466.

It can be written as a sum of positive squares in 2 ways, for example, as 6568940401 + 71318025 = 81049^2 + 8445^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37686 + ... + 121246.

Almost surely, 2^6640258426 is an apocalyptic number.

6640258426 is a deficient number, since it is larger than the sum of its proper divisors (3320499098).

6640258426 is a wasteful number, since it uses less digits than its factorization.

6640258426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123296.

The product of its (nonzero) digits is 552960, while the sum is 43.

The square root of 6640258426 is about 81487.7808386018. The cubic root of 6640258426 is about 1879.5836585591.

The spelling of 6640258426 in words is "six billion, six hundred forty million, two hundred fifty-eight thousand, four hundred twenty-six".