78145440 has 96 divisors (see below), whose sum is σ = 249734016. Its totient is φ = 20536320.

The previous prime is 78145439. The next prime is 78145523. The reversal of 78145440 is 4454187.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×78145440² = 12213419585587200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32934 + ... + 35226.

It is an arithmetic number, because the mean of its divisors is an integer number (2601396).

Almost surely, 2^78145440 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 78145440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124867008).

78145440 is an abundant number, since it is smaller than the sum of its proper divisors (171588576).

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

78145440 is a wasteful number, since it uses less digits than its factorization.

78145440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2382 (or 2374 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 33.

The square root of 78145440 is about 8839.9909502216. The cubic root of 78145440 is about 427.5312654538.

The spelling of 78145440 in words is "seventy-eight million, one hundred forty-five thousand, four hundred forty".