78321431 has 8 divisors (see below), whose sum is σ = 85788720. Its totient is φ = 71171968.

The previous prime is 78321413. The next prime is 78321443. The reversal of 78321431 is 13412387.

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 78321431 - 2¹⁸ = 78059287 is a prime.

It is a super-2 number, since 2×78321431² = 12268493107775522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78321394 and 78321403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78321461) 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, 78941 + ... + 79926.

It is an arithmetic number, because the mean of its divisors is an integer number (10723590).

Almost surely, 2^78321431 is an apocalyptic number.

78321431 is a deficient number, since it is larger than the sum of its proper divisors (7467289).

78321431 is a wasteful number, since it uses less digits than its factorization.

78321431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158913.

The product of its digits is 4032, while the sum is 29.

The square root of 78321431 is about 8849.9396043137. The cubic root of 78321431 is about 427.8519719114.

The spelling of 78321431 in words is "seventy-eight million, three hundred twenty-one thousand, four hundred thirty-one".