78640632 has 96 divisors (see below), whose sum is σ = 252470400. Its totient is φ = 22464864.

The previous prime is 78640631. The next prime is 78640633. The reversal of 78640632 is 23604687.

78640632 is a `hidden beast` number, since 7 + 8 + 640 + 6 + 3 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (78640631) and next prime (78640633).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78640631) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10719 + ... + 16497.

It is an arithmetic number, because the mean of its divisors is an integer number (2629900).

Almost surely, 2^78640632 is an apocalyptic number.

78640632 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 78640632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126235200).

78640632 is an abundant number, since it is smaller than the sum of its proper divisors (173829768).

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

78640632 is a wasteful number, since it uses less digits than its factorization.

78640632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5807 (or 5791 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 78640632 is about 8867.9553449485. The cubic root of 78640632 is about 428.4324246343.

The spelling of 78640632 in words is "seventy-eight million, six hundred forty thousand, six hundred thirty-two".