787664 has 20 divisors (see below), whose sum is σ = 1607040. Its totient is φ = 372960.

The previous prime is 787649. The next prime is 787667. The reversal of 787664 is 466787.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (787667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 992 + ... + 1599.

It is an arithmetic number, because the mean of its divisors is an integer number (80352).

2⁷⁸⁷⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

787664 is an abundant number, since it is smaller than the sum of its proper divisors (819376).

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

787664 is a wasteful number, since it uses less digits than its factorization.

787664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2618 (or 2612 counting only the distinct ones).

The product of its digits is 56448, while the sum is 38.

The square root of 787664 is about 887.5043661864. The cubic root of 787664 is about 92.3521475329.

The spelling of 787664 in words is "seven hundred eighty-seven thousand, six hundred sixty-four".