78626640 has 80 divisors (see below), whose sum is σ = 245127168. Its totient is φ = 20848128.

The previous prime is 78626623. The next prime is 78626657. The reversal of 78626640 is 4662687.

It is an interprime number because it is at equal distance from previous prime (78626623) and next prime (78626657).

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46449 + ... + 48111.

Almost surely, 2^78626640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78626640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122563584).

78626640 is an abundant number, since it is smaller than the sum of its proper divisors (166500528).

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

78626640 is a wasteful number, since it uses less digits than its factorization.

78626640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1876 (or 1870 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 39.

The square root of 78626640 is about 8867.1664019573. The cubic root of 78626640 is about 428.4070137583.

The spelling of 78626640 in words is "seventy-eight million, six hundred twenty-six thousand, six hundred forty".