6642240257 has 8 divisors (see below), whose sum is σ = 6752056320. Its totient is φ = 6533206240.

The previous prime is 6642240251. The next prime is 6642240263. The reversal of 6642240257 is 7520422466.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (6642240251) and next prime (6642240263).

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

It is a cyclic number.

It is not a de Polignac number, because 6642240257 - 2⁶ = 6642240193 is a prime.

It is a super-2 number, since 2×6642240257² = 88238711263422852098, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6642240257.

It is not an unprimeable number, because it can be changed into a prime (6642240251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 178373 + ... + 212370.

It is an arithmetic number, because the mean of its divisors is an integer number (844007040).

Almost surely, 2^6642240257 is an apocalyptic number.

It is an amenable number.

6642240257 is a deficient number, since it is larger than the sum of its proper divisors (109816063).

6642240257 is a wasteful number, since it uses less digits than its factorization.

6642240257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391023.

The product of its (nonzero) digits is 161280, while the sum is 38.

The square root of 6642240257 is about 81499.9402269719. The cubic root of 6642240257 is about 1879.7706315350.

The spelling of 6642240257 in words is "six billion, six hundred forty-two million, two hundred forty thousand, two hundred fifty-seven".