78326891 has 8 divisors (see below), whose sum is σ = 83942304. Its totient is φ = 72895680.

The previous prime is 78326881. The next prime is 78326971. The reversal of 78326891 is 19862387.

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 78326891 - 2¹⁸ = 78064747 is a prime.

It is a super-2 number, since 2×78326891² = 12270203707451762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78326861) 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, 45170 + ... + 46871.

It is an arithmetic number, because the mean of its divisors is an integer number (10492788).

Almost surely, 2^78326891 is an apocalyptic number.

78326891 is a deficient number, since it is larger than the sum of its proper divisors (5615413).

78326891 is a wasteful number, since it uses less digits than its factorization.

78326891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92101.

The product of its digits is 145152, while the sum is 44.

The square root of 78326891 is about 8850.2480756191. The cubic root of 78326891 is about 427.8619139219.

The spelling of 78326891 in words is "seventy-eight million, three hundred twenty-six thousand, eight hundred ninety-one".