78842131 has 4 divisors (see below), whose sum is σ = 79045200. Its totient is φ = 78639064.

The previous prime is 78842123. The next prime is 78842143. The reversal of 78842131 is 13124887.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 78842131 - 2³ = 78842123 is a prime.

It is a super-2 number, since 2×78842131² = 12432163241242322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78842431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100951 + ... + 101728.

It is an arithmetic number, because the mean of its divisors is an integer number (19761300).

Almost surely, 2^78842131 is an apocalyptic number.

78842131 is a deficient number, since it is larger than the sum of its proper divisors (203069).

78842131 is a wasteful number, since it uses less digits than its factorization.

78842131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203068.

The product of its digits is 10752, while the sum is 34.

The square root of 78842131 is about 8879.3091510545. The cubic root of 78842131 is about 428.7980332476.

The spelling of 78842131 in words is "seventy-eight million, eight hundred forty-two thousand, one hundred thirty-one".