77766620 has 36 divisors (see below), whose sum is σ = 172373544. Its totient is φ = 29466720.

The previous prime is 77766617. The next prime is 77766629. The reversal of 77766620 is 2666777.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77766629) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1835 + ... + 12605.

It is an arithmetic number, because the mean of its divisors is an integer number (4788154).

Almost surely, 2^77766620 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 77766620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86186772).

77766620 is an abundant number, since it is smaller than the sum of its proper divisors (94606924).

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

77766620 is a wasteful number, since it uses less digits than its factorization.

77766620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10818 (or 10797 counting only the distinct ones).

The product of its (nonzero) digits is 148176, while the sum is 41.

The square root of 77766620 is about 8818.5384276534. The cubic root of 77766620 is about 426.8393086610.

The spelling of 77766620 in words is "seventy-seven million, seven hundred sixty-six thousand, six hundred twenty".