77021664 has 48 divisors (see below), whose sum is σ = 210978432. Its totient is φ = 24556928.

The previous prime is 77021647. The next prime is 77021669. The reversal of 77021664 is 46612077.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77021669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15234 + ... + 19649.

It is an arithmetic number, because the mean of its divisors is an integer number (4395384).

Almost surely, 2^77021664 is an apocalyptic number.

It is an amenable number.

77021664 is an abundant number, since it is smaller than the sum of its proper divisors (133956768).

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

77021664 is a wasteful number, since it uses less digits than its factorization.

77021664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34919 (or 34911 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 33.

The square root of 77021664 is about 8776.1987215423. The cubic root of 77021664 is about 425.4719813015.

The spelling of 77021664 in words is "seventy-seven million, twenty-one thousand, six hundred sixty-four".