78234420 has 96 divisors (see below), whose sum is σ = 241315200. Its totient is φ = 18780160.

The previous prime is 78234397. The next prime is 78234427. The reversal of 78234420 is 2443287.

It is a super-2 number, since 2×78234420² = 12241248945472800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78234427) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 74056 + ... + 75104.

It is an arithmetic number, because the mean of its divisors is an integer number (2513700).

Almost surely, 2^78234420 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 78234420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120657600).

78234420 is an abundant number, since it is smaller than the sum of its proper divisors (163080780).

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

78234420 is a wasteful number, since it uses less digits than its factorization.

78234420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1185 (or 1183 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 30.

The square root of 78234420 is about 8845.0223289713. The cubic root of 78234420 is about 427.6934728389.

The spelling of 78234420 in words is "seventy-eight million, two hundred thirty-four thousand, four hundred twenty".