78404233 has 2 divisors, whose sum is σ = 78404234. Its totient is φ = 78404232.

The previous prime is 78404231. The next prime is 78404243. The reversal of 78404233 is 33240487.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69422224 + 8982009 = 8332^2 + 2997^2 .

It is a cyclic number.

It is not a de Polignac number, because 78404233 - 2¹ = 78404231 is a prime.

It is a super-2 number, since 2×78404233² = 12294447504636578, which contains 22 as substring.

Together with 78404231, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 78404195 and 78404204.

It is not a weakly prime, because it can be changed into another prime (78404231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39202116 + 39202117.

It is an arithmetic number, because the mean of its divisors is an integer number (39202117).

Almost surely, 2^78404233 is an apocalyptic number.

It is an amenable number.

78404233 is a deficient number, since it is larger than the sum of its proper divisors (1).

78404233 is an equidigital number, since it uses as much as digits as its factorization.

78404233 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 78404233 is about 8854.6164795546. The cubic root of 78404233 is about 428.0026949054.

The spelling of 78404233 in words is "seventy-eight million, four hundred four thousand, two hundred thirty-three".