78473939 has 4 divisors (see below), whose sum is σ = 79467360. Its totient is φ = 77480520.

The previous prime is 78473903. The next prime is 78473987. The reversal of 78473939 is 93937487.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78473939 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (78475939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 496592 + ... + 496749.

It is an arithmetic number, because the mean of its divisors is an integer number (19866840).

Almost surely, 2^78473939 is an apocalyptic number.

78473939 is a gapful number since it is divisible by the number (79) formed by its first and last digit.

78473939 is a deficient number, since it is larger than the sum of its proper divisors (993421).

78473939 is an equidigital number, since it uses as much as digits as its factorization.

78473939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 993420.

The product of its digits is 1143072, while the sum is 50.

The square root of 78473939 is about 8858.5517439365. The cubic root of 78473939 is about 428.1294972373.

The spelling of 78473939 in words is "seventy-eight million, four hundred seventy-three thousand, nine hundred thirty-nine".