78389136 has 120 divisors (see below), whose sum is σ = 263981120. Its totient is φ = 21212928.

The previous prime is 78389131. The next prime is 78389161. The reversal of 78389136 is 63198387.

It is a happy number.

It is a super-2 number, since 2×78389136² = 12289713285652992, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 78389091 and 78389100.

It is not an unprimeable number, because it can be changed into a prime (78389131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17106 + ... + 21198.

Almost surely, 2^78389136 is an apocalyptic number.

78389136 is a gapful number since it is divisible by the number (76) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78389136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131990560).

78389136 is an abundant number, since it is smaller than the sum of its proper divisors (185591984).

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

78389136 is a wasteful number, since it uses less digits than its factorization.

78389136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4133 (or 4124 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 78389136 is about 8853.7639453512. The cubic root of 78389136 is about 427.9752220203.

The spelling of 78389136 in words is "seventy-eight million, three hundred eighty-nine thousand, one hundred thirty-six".