78290823 has 16 divisors (see below), whose sum is σ = 112624736. Its totient is φ = 48090240.

The previous prime is 78290819. The next prime is 78290837. The reversal of 78290823 is 32809287.

It is not a de Polignac number, because 78290823 - 2² = 78290819 is a prime.

It is a super-2 number, since 2×78290823² = 12258905932034658, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78290803) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24261 + ... + 27297.

It is an arithmetic number, because the mean of its divisors is an integer number (7039046).

Almost surely, 2^78290823 is an apocalyptic number.

78290823 is a deficient number, since it is larger than the sum of its proper divisors (34333913).

78290823 is a wasteful number, since it uses less digits than its factorization.

78290823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3714.

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 78290823 is about 8848.2101579924. The cubic root of 78290823 is about 427.7962298269.

Subtracting from 78290823 its reverse (32809287), we obtain a square (45481536 = 6744²).

The spelling of 78290823 in words is "seventy-eight million, two hundred ninety thousand, eight hundred twenty-three".