6426640022440 has 64 divisors (see below), whose sum is σ = 15776090712000. Its totient is φ = 2336721392640.

The previous prime is 6426640022431. The next prime is 6426640022449. The reversal of 6426640022440 is 442200466246.

It is an interprime number because it is at equal distance from previous prime (6426640022431) and next prime (6426640022449).

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 = 6426640022393 and 6426640022402.

It is not an unprimeable number, because it can be changed into a prime (6426640022449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3597216 + ... + 5078704.

It is an arithmetic number, because the mean of its divisors is an integer number (246501417375).

Almost surely, 2^{6426640022440} is an apocalyptic number.

It is an amenable number.

6426640022440 is an abundant number, since it is smaller than the sum of its proper divisors (9349450689560).

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

6426640022440 is a wasteful number, since it uses less digits than its factorization.

6426640022440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1491370 (or 1491366 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 40.

Adding to 6426640022440 its reverse (442200466246), we get a palindrome (6868840488686).

The spelling of 6426640022440 in words is "six trillion, four hundred twenty-six billion, six hundred forty million, twenty-two thousand, four hundred forty".