78533905 has 4 divisors (see below), whose sum is σ = 94240692. Its totient is φ = 62827120.

The previous prime is 78533899. The next prime is 78533927. The reversal of 78533905 is 50933587.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18378369 + 60155536 = 4287^2 + 7756^2 .

It is not a de Polignac number, because 78533905 - 2⁹ = 78533393 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7853386 + ... + 7853395.

It is an arithmetic number, because the mean of its divisors is an integer number (23560173).

Almost surely, 2^78533905 is an apocalyptic number.

It is an amenable number.

78533905 is a deficient number, since it is larger than the sum of its proper divisors (15706787).

78533905 is a wasteful number, since it uses less digits than its factorization.

78533905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15706786.

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 78533905 is about 8861.9357366210. The cubic root of 78533905 is about 428.2385214438.

The spelling of 78533905 in words is "seventy-eight million, five hundred thirty-three thousand, nine hundred five".