78017940 has 288 divisors, whose sum is σ = 318479616. Its totient is φ = 14929920.

The previous prime is 78017923. The next prime is 78017969. The reversal of 78017940 is 4971087.

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 = 78017895 and 78017904.

It is a congruent number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 179964 + ... + 180396.

It is an arithmetic number, because the mean of its divisors is an integer number (1105832).

Almost surely, 2^78017940 is an apocalyptic number.

78017940 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78017940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159239808).

78017940 is an abundant number, since it is smaller than the sum of its proper divisors (240461676).

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

78017940 is a wasteful number, since it uses less digits than its factorization.

78017940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 479 (or 474 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 78017940 is about 8832.7764604342. The cubic root of 78017940 is about 427.2986227086.

The spelling of 78017940 in words is "seventy-eight million, seventeen thousand, nine hundred forty".