78431889 has 8 divisors (see below), whose sum is σ = 104850432. Its totient is φ = 52150640.

The previous prime is 78431887. The next prime is 78431917. The reversal of 78431889 is 98813487.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78431889 - 2¹ = 78431887 is a prime.

It is a super-2 number, since 2×78431889² = 12303122424216642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78431887) 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, 32982 + ... + 35279.

It is an arithmetic number, because the mean of its divisors is an integer number (13106304).

Almost surely, 2^78431889 is an apocalyptic number.

It is an amenable number.

78431889 is a deficient number, since it is larger than the sum of its proper divisors (26418543).

78431889 is a wasteful number, since it uses less digits than its factorization.

78431889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68647.

The product of its digits is 387072, while the sum is 48.

The square root of 78431889 is about 8856.1780131160. The cubic root of 78431889 is about 428.0530129839.

The spelling of 78431889 in words is "seventy-eight million, four hundred thirty-one thousand, eight hundred eighty-nine".