777777660 has 192 divisors, whose sum is σ = 2754984960. Its totient is φ = 180322560.

The previous prime is 777777653. The next prime is 777777677. The reversal of 777777660 is 66777777.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 777777597 and 777777606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 133774 + ... + 139466.

It is an arithmetic number, because the mean of its divisors is an integer number (14348880).

Almost surely, 2^777777660 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 777777660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1377492480).

777777660 is an abundant number, since it is smaller than the sum of its proper divisors (1977207300).

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

777777660 is a wasteful number, since it uses less digits than its factorization.

777777660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5745 (or 5737 counting only the distinct ones).

The product of its (nonzero) digits is 4235364, while the sum is 54.

The square root of 777777660 is about 27888.6654395652. The cubic root of 777777660 is about 919.6413457070.

The spelling of 777777660 in words is "seven hundred seventy-seven million, seven hundred seventy-seven thousand, six hundred sixty".