78438236 has 6 divisors (see below), whose sum is σ = 137266920. Its totient is φ = 39219116.

The previous prime is 78438233. The next prime is 78438259. The reversal of 78438236 is 63283487.

It is a junction number, because it is equal to n+sod(n) for n = 78438193 and 78438202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78438233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9804776 + ... + 9804783.

It is an arithmetic number, because the mean of its divisors is an integer number (22877820).

Almost surely, 2^78438236 is an apocalyptic number.

It is an amenable number.

78438236 is a deficient number, since it is larger than the sum of its proper divisors (58828684).

78438236 is a wasteful number, since it uses less digits than its factorization.

78438236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19609563 (or 19609561 counting only the distinct ones).

The product of its digits is 193536, while the sum is 41.

The square root of 78438236 is about 8856.5363432891. The cubic root of 78438236 is about 428.0645592194.

The spelling of 78438236 in words is "seventy-eight million, four hundred thirty-eight thousand, two hundred thirty-six".