6396766640 has 120 divisors (see below), whose sum is σ = 16911886320. Its totient is φ = 2245788160.

The previous prime is 6396766639. The next prime is 6396766657. The reversal of 6396766640 is 466676936.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 269327 + ... + 292113.

It is an arithmetic number, because the mean of its divisors is an integer number (140932386).

Almost surely, 2^6396766640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6396766640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8455943160).

6396766640 is an abundant number, since it is smaller than the sum of its proper divisors (10515119680).

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

6396766640 is a wasteful number, since it uses less digits than its factorization.

6396766640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22851 (or 22834 counting only the distinct ones).

The product of its (nonzero) digits is 5878656, while the sum is 53.

The square root of 6396766640 is about 79979.7889469583. The cubic root of 6396766640 is about 1856.3228156164.

The spelling of 6396766640 in words is "six billion, three hundred ninety-six million, seven hundred sixty-six thousand, six hundred forty".