77428512 has 144 divisors (see below), whose sum is σ = 254217600. Its totient is φ = 21897216.

The previous prime is 77428501. The next prime is 77428567. The reversal of 77428512 is 21582477.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 388989 + ... + 389187.

It is an arithmetic number, because the mean of its divisors is an integer number (1765400).

Almost surely, 2^77428512 is an apocalyptic number.

77428512 is a gapful number since it is divisible by the number (72) 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 77428512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127108800).

77428512 is an abundant number, since it is smaller than the sum of its proper divisors (176789088).

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

77428512 is a wasteful number, since it uses less digits than its factorization.

77428512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415 (or 404 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 77428512 is about 8799.3472485179. The cubic root of 77428512 is about 426.2198164630.

The spelling of 77428512 in words is "seventy-seven million, four hundred twenty-eight thousand, five hundred twelve".