78071640 has 96 divisors (see below), whose sum is σ = 242371440. Its totient is φ = 20117760.

The previous prime is 78071639. The next prime is 78071641. The reversal of 78071640 is 4617087.

It is an interprime number because it is at equal distance from previous prime (78071639) and next prime (78071641).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78071641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 114982 + ... + 115658.

Almost surely, 2^78071640 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 78071640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121185720).

78071640 is an abundant number, since it is smaller than the sum of its proper divisors (164299800).

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

78071640 is a wasteful number, since it uses less digits than its factorization.

78071640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 753 (or 718 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 78071640 is about 8835.8157518138. The cubic root of 78071640 is about 427.3966372314.

The spelling of 78071640 in words is "seventy-eight million, seventy-one thousand, six hundred forty".