7761656640 has 112 divisors (see below), whose sum is σ = 24752515392. Its totient is φ = 2060599296.

The previous prime is 7761656633. The next prime is 7761656641. The reversal of 7761656640 is 466561677.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 7761656640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7761656641) 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, 200112 + ... + 235728.

Almost surely, 2^7761656640 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 7761656640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12376257696).

7761656640 is an abundant number, since it is smaller than the sum of its proper divisors (16990858752).

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

7761656640 is a wasteful number, since it uses less digits than its factorization.

7761656640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35864 (or 35854 counting only the distinct ones).

The product of its (nonzero) digits is 1270080, while the sum is 48.

The square root of 7761656640 is about 88100.2646988078. The cubic root of 7761656640 is about 1979.9374737933.

The spelling of 7761656640 in words is "seven billion, seven hundred sixty-one million, six hundred fifty-six thousand, six hundred forty".