78440292 has 96 divisors (see below), whose sum is σ = 239984640. Its totient is φ = 21682080.

The previous prime is 78440291. The next prime is 78440357. The reversal of 78440292 is 29204487.

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 (78440291) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21763 + ... + 25109.

It is an arithmetic number, because the mean of its divisors is an integer number (2499840).

Almost surely, 2^78440292 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 78440292, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119992320).

78440292 is an abundant number, since it is smaller than the sum of its proper divisors (161544348).

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

78440292 is a wasteful number, since it uses less digits than its factorization.

78440292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3398 (or 3390 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 78440292 is about 8856.6524149929. The cubic root of 78440292 is about 428.0682992876.

The spelling of 78440292 in words is "seventy-eight million, four hundred forty thousand, two hundred ninety-two".