6626997990 has 80 divisors (see below), whose sum is σ = 17853031152. Its totient is φ = 1763850816.

The previous prime is 6626997947. The next prime is 6626997991. The reversal of 6626997990 is 997996266.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6626997991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 435592 + ... + 450548.

Almost surely, 2^6626997990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6626997990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8926515576).

6626997990 is an abundant number, since it is smaller than the sum of its proper divisors (11226033162).

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

6626997990 is a wasteful number, since it uses less digits than its factorization.

6626997990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15523 (or 15514 counting only the distinct ones).

The product of its (nonzero) digits is 19840464, while the sum is 63.

The square root of 6626997990 is about 81406.3756102678. The cubic root of 6626997990 is about 1878.3316637027.

The spelling of 6626997990 in words is "six billion, six hundred twenty-six million, nine hundred ninety-seven thousand, nine hundred ninety".