78816249 has 12 divisors (see below), whose sum is σ = 113922900. Its totient is φ = 52508544.

The previous prime is 78816203. The next prime is 78816263. The reversal of 78816249 is 94261887.

It can be written as a sum of positive squares in 2 ways, for example, as 63489024 + 15327225 = 7968^2 + 3915^2 .

It is not a de Polignac number, because 78816249 - 2¹¹ = 78814201 is a prime.

It is a super-2 number, since 2×78816249² = 12424002212860002, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78816289) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22957 + ... + 26165.

It is an arithmetic number, because the mean of its divisors is an integer number (9493575).

Almost surely, 2^78816249 is an apocalyptic number.

It is an amenable number.

78816249 is a deficient number, since it is larger than the sum of its proper divisors (35106651).

78816249 is a wasteful number, since it uses less digits than its factorization.

78816249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5944 (or 5941 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 78816249 is about 8877.8515982190. The cubic root of 78816249 is about 428.7511067072.

The spelling of 78816249 in words is "seventy-eight million, eight hundred sixteen thousand, two hundred forty-nine".