78260640 has 96 divisors (see below), whose sum is σ = 251838720. Its totient is φ = 20419584.

The previous prime is 78260629. The next prime is 78260657. The reversal of 78260640 is 4606287.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×78260640² = 12249455546419200, which contains 22 as substring.

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, 20826 + ... + 24294.

It is an arithmetic number, because the mean of its divisors is an integer number (2623320).

Almost surely, 2^78260640 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 78260640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125919360).

78260640 is an abundant number, since it is smaller than the sum of its proper divisors (173578080).

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

78260640 is a wasteful number, since it uses less digits than its factorization.

78260640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3534 (or 3526 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 78260640 is about 8846.5043943922. The cubic root of 78260640 is about 427.7412475068.

The spelling of 78260640 in words is "seventy-eight million, two hundred sixty thousand, six hundred forty".