777680640 has 648 divisors, whose sum is σ = 3280153968. Its totient is φ = 168099840.

The previous prime is 777680639. The next prime is 777680641. The reversal of 777680640 is 46086777.

It is an interprime number because it is at equal distance from previous prime (777680639) and next prime (777680641).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (777680641) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 40930551 + ... + 40930569.

It is an arithmetic number, because the mean of its divisors is an integer number (5061966).

Almost surely, 2^777680640 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 777680640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1640076984).

777680640 is an abundant number, since it is smaller than the sum of its proper divisors (2502473328).

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

777680640 is a wasteful number, since it uses less digits than its factorization.

777680640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 395136, while the sum is 45.

The square root of 777680640 is about 27886.9259689913. The cubic root of 777680640 is about 919.6031054240.

The spelling of 777680640 in words is "seven hundred seventy-seven million, six hundred eighty thousand, six hundred forty".