78981814 has 4 divisors (see below), whose sum is σ = 118472724. Its totient is φ = 39490906.

The previous prime is 78981797. The next prime is 78981821. The reversal of 78981814 is 41818987.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 41818987 = 7 ⋅5974141.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19745452 + ... + 19745455.

It is an arithmetic number, because the mean of its divisors is an integer number (29618181).

Almost surely, 2^78981814 is an apocalyptic number.

78981814 is a deficient number, since it is larger than the sum of its proper divisors (39490910).

78981814 is a wasteful number, since it uses less digits than its factorization.

78981814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39490909.

The product of its digits is 129024, while the sum is 46.

The square root of 78981814 is about 8887.1713160038. The cubic root of 78981814 is about 429.0511147648.

The spelling of 78981814 in words is "seventy-eight million, nine hundred eighty-one thousand, eight hundred fourteen".