78398 has 4 divisors (see below), whose sum is σ = 117600. Its totient is φ = 39198.

The previous prime is 78367. The next prime is 78401. The reversal of 78398 is 89387.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×78398² = 12292492808, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

78398 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19598 + ... + 19601.

It is an arithmetic number, because the mean of its divisors is an integer number (29400).

2⁷⁸³⁹⁸ is an apocalyptic number.

78398 is a deficient number, since it is larger than the sum of its proper divisors (39202).

78398 is a wasteful number, since it uses less digits than its factorization.

78398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39201.

The product of its digits is 12096, while the sum is 35.

The square root of 78398 is about 279.9964285487. The cubic root of 78398 is about 42.7991352782.

The spelling of 78398 in words is "seventy-eight thousand, three hundred ninety-eight".