78287400 has 288 divisors, whose sum is σ = 287838720. Its totient is φ = 19008000.

The previous prime is 78287393. The next prime is 78287401. The reversal of 78287400 is 478287.

It is a super-2 number, since 2×78287400² = 12257833997520000, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (78287401) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1283370 + ... + 1283430.

It is an arithmetic number, because the mean of its divisors is an integer number (999440).

Almost surely, 2^78287400 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 78287400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143919360).

78287400 is an abundant number, since it is smaller than the sum of its proper divisors (209551320).

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

78287400 is a wasteful number, since it uses less digits than its factorization.

78287400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 36.

The square root of 78287400 is about 8848.0167269281. The cubic root of 78287400 is about 427.7899950909.

It can be divided in two parts, 78287 and 400, that added together give a palindrome (78687).

The spelling of 78287400 in words is "seventy-eight million, two hundred eighty-seven thousand, four hundred".