78398134 has 4 divisors (see below), whose sum is σ = 117597204. Its totient is φ = 39199066.

The previous prime is 78398087. The next prime is 78398137. The reversal of 78398134 is 43189387.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 43189387 = 137 ⋅315251.

It is a super-2 number, since 2×78398134² = 12292534829363912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78398137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19599532 + ... + 19599535.

It is an arithmetic number, because the mean of its divisors is an integer number (29399301).

Almost surely, 2^78398134 is an apocalyptic number.

78398134 is a deficient number, since it is larger than the sum of its proper divisors (39199070).

78398134 is a wasteful number, since it uses less digits than its factorization.

78398134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39199069.

The product of its digits is 145152, while the sum is 43.

The square root of 78398134 is about 8854.2720762353. The cubic root of 78398134 is about 427.9915966266.

The spelling of 78398134 in words is "seventy-eight million, three hundred ninety-eight thousand, one hundred thirty-four".