6642626440 has 64 divisors (see below), whose sum is σ = 15057750960. Its totient is φ = 2637250560.

The previous prime is 6642626399. The next prime is 6642626467. The reversal of 6642626440 is 446262466.

It can be written as a sum of positive squares in 8 ways, for example, as 6062491044 + 580135396 = 77862^2 + 24086^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 6642626393 and 6642626402.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3292312 + ... + 3294328.

Almost surely, 2^6642626440 is an apocalyptic number.

It is an amenable number.

6642626440 is an abundant number, since it is smaller than the sum of its proper divisors (8415124520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6642626440 is a wasteful number, since it uses less digits than its factorization.

6642626440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2602 (or 2598 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 40.

The square root of 6642626440 is about 81502.3094151325. The cubic root of 6642626440 is about 1879.8070610812.

The spelling of 6642626440 in words is "six billion, six hundred forty-two million, six hundred twenty-six thousand, four hundred forty".