78788788 has 12 divisors (see below), whose sum is σ = 148486660. Its totient is φ = 36364032.

The previous prime is 78788767. The next prime is 78788789. The reversal of 78788788 is 88788787.

It can be written as a sum of positive squares in 2 ways, for example, as 41113744 + 37675044 = 6412^2 + 6138^2 .

It is a super-2 number, since 2×78788788² = 12415346229017888, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78788789) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 757533 + ... + 757636.

Almost surely, 2^78788788 is an apocalyptic number.

It is an amenable number.

78788788 is a deficient number, since it is larger than the sum of its proper divisors (69697872).

78788788 is a wasteful number, since it uses less digits than its factorization.

78788788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1515186 (or 1515184 counting only the distinct ones).

The product of its digits is 11239424, while the sum is 61.

The square root of 78788788 is about 8876.3048618217. The cubic root of 78788788 is about 428.7013060550.

Subtracting 78788788 from its reverse (88788787), we obtain a palindrome (9999999).

The spelling of 78788788 in words is "seventy-eight million, seven hundred eighty-eight thousand, seven hundred eighty-eight".