78459840 has 168 divisors, whose sum is σ = 280141680. Its totient is φ = 20901888.

The previous prime is 78459827. The next prime is 78459841. The reversal of 78459840 is 4895487.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78459841) 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, 77256 + ... + 78264.

It is an arithmetic number, because the mean of its divisors is an integer number (1667510).

Almost surely, 2^78459840 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 78459840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140070840).

78459840 is an abundant number, since it is smaller than the sum of its proper divisors (201681840).

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

78459840 is a wasteful number, since it uses less digits than its factorization.

78459840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041 (or 1019 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The square root of 78459840 is about 8857.7559234831. The cubic root of 78459840 is about 428.1038557764.

The spelling of 78459840 in words is "seventy-eight million, four hundred fifty-nine thousand, eight hundred forty".