78751440 has 120 divisors (see below), whose sum is σ = 274336608. Its totient is φ = 20995200.

The previous prime is 78751433. The next prime is 78751459. The reversal of 78751440 is 4415787.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 78751395 and 78751404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17415 + ... + 21465.

Almost surely, 2^78751440 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 78751440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137168304).

78751440 is an abundant number, since it is smaller than the sum of its proper divisors (195585168).

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

78751440 is a wasteful number, since it uses less digits than its factorization.

78751440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4079 (or 4061 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 36.

The square root of 78751440 is about 8874.2008090870. The cubic root of 78751440 is about 428.6335567074.

The spelling of 78751440 in words is "seventy-eight million, seven hundred fifty-one thousand, four hundred forty".