77664220 has 12 divisors (see below), whose sum is σ = 163094904. Its totient is φ = 31065680.

The previous prime is 77664203. The next prime is 77664227. The reversal of 77664220 is 2246677.

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 (77664227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1941586 + ... + 1941625.

It is an arithmetic number, because the mean of its divisors is an integer number (13591242).

Almost surely, 2^77664220 is an apocalyptic number.

It is an amenable number.

77664220 is an abundant number, since it is smaller than the sum of its proper divisors (85430684).

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

77664220 is a wasteful number, since it uses less digits than its factorization.

77664220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3883220 (or 3883218 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 34.

The square root of 77664220 is about 8812.7305643597. The cubic root of 77664220 is about 426.6518780139.

The spelling of 77664220 in words is "seventy-seven million, six hundred sixty-four thousand, two hundred twenty".