78123580 has 24 divisors (see below), whose sum is σ = 164546928. Its totient is φ = 31156608.

The previous prime is 78123559. The next prime is 78123581. The reversal of 78123580 is 8532187.

It is a super-2 number, since 2×78123580² = 12206587504032800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78123581) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1312 + ... + 12568.

It is an arithmetic number, because the mean of its divisors is an integer number (6856122).

Almost surely, 2^78123580 is an apocalyptic number.

It is an amenable number.

78123580 is an abundant number, since it is smaller than the sum of its proper divisors (86423348).

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

78123580 is a wasteful number, since it uses less digits than its factorization.

78123580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11613 (or 11611 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 78123580 is about 8838.7544371365. The cubic root of 78123580 is about 427.4913966099.

The spelling of 78123580 in words is "seventy-eight million, one hundred twenty-three thousand, five hundred eighty".