78921296 has 40 divisors (see below), whose sum is σ = 162493320. Its totient is φ = 37062144.

The previous prime is 78921289. The next prime is 78921301. The reversal of 78921296 is 69212987.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10627600 + 68293696 = 3260^2 + 8264^2 .

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14870 + ... + 19466.

It is an arithmetic number, because the mean of its divisors is an integer number (4062333).

Almost surely, 2^78921296 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 78921296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81246660).

78921296 is an abundant number, since it is smaller than the sum of its proper divisors (83572024).

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

78921296 is a wasteful number, since it uses less digits than its factorization.

78921296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4671 (or 4665 counting only the distinct ones).

The product of its digits is 108864, while the sum is 44.

The square root of 78921296 is about 8883.7658681440. The cubic root of 78921296 is about 428.9415032452.

The spelling of 78921296 in words is "seventy-eight million, nine hundred twenty-one thousand, two hundred ninety-six".