78240136 has 64 divisors (see below), whose sum is σ = 165110400. Its totient is φ = 34521600.

The previous prime is 78240109. The next prime is 78240179. The reversal of 78240136 is 63104287.

It is a super-2 number, since 2×78240136² = 12243037762596992, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78240098 and 78240107.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 251421 + ... + 251731.

It is an arithmetic number, because the mean of its divisors is an integer number (2579850).

Almost surely, 2^78240136 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 78240136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82555200).

78240136 is an abundant number, since it is smaller than the sum of its proper divisors (86870264).

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

78240136 is a wasteful number, since it uses less digits than its factorization.

78240136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430 (or 426 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 78240136 is about 8845.3454426608. The cubic root of 78240136 is about 427.7038886992.

The spelling of 78240136 in words is "seventy-eight million, two hundred forty thousand, one hundred thirty-six".