7779313664640 has 1056 divisors, whose sum is σ = 32458144488660. Its totient is φ = 1777705574400.

The previous prime is 7779313664609. The next prime is 7779313664701. The reversal of 7779313664640 is 464663139777.

7779313664640 is a `hidden beast` number, since 7 + 77 + 93 + 13 + 6 + 6 + 464 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 6897682806336 + 881630858304 = 2626344^2 + 938952^2 .

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 131 ways as a sum of consecutive naturals, for example, 1851774540 + ... + 1851778740.

Almost surely, 2^{7779313664640} is an apocalyptic number.

7779313664640 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7779313664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16229072244330).

7779313664640 is an abundant number, since it is smaller than the sum of its proper divisors (24678830824020).

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

7779313664640 is an frugal number, since it uses more digits than its factorization.

7779313664640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4264 (or 4218 counting only the distinct ones).

The product of its (nonzero) digits is 96018048, while the sum is 63.

The spelling of 7779313664640 in words is "seven trillion, seven hundred seventy-nine billion, three hundred thirteen million, six hundred sixty-four thousand, six hundred forty".