78347420 has 24 divisors (see below), whose sum is σ = 165990384. Its totient is φ = 31060736.

The previous prime is 78347387. The next prime is 78347429. The reversal of 78347420 is 2474387.

It is a super-2 number, since 2×78347420² = 12276636441312800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78347429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15074 + ... + 19593.

It is an arithmetic number, because the mean of its divisors is an integer number (6916266).

Almost surely, 2^78347420 is an apocalyptic number.

It is an amenable number.

78347420 is an abundant number, since it is smaller than the sum of its proper divisors (87642964).

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

78347420 is a wasteful number, since it uses less digits than its factorization.

78347420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34789 (or 34787 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 35.

The square root of 78347420 is about 8851.4077976331. The cubic root of 78347420 is about 427.8992906553.

The spelling of 78347420 in words is "seventy-eight million, three hundred forty-seven thousand, four hundred twenty".