78648173 has 4 divisors (see below), whose sum is σ = 78666588. Its totient is φ = 78629760.

The previous prime is 78648139. The next prime is 78648233. The reversal of 78648173 is 37184687.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 37184687 = 3947 ⋅9421.

It can be written as a sum of positive squares in 2 ways, for example, as 65237929 + 13410244 = 8077^2 + 3662^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78648173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78642173) 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, 893 + ... + 12573.

It is an arithmetic number, because the mean of its divisors is an integer number (19666647).

Almost surely, 2^78648173 is an apocalyptic number.

It is an amenable number.

78648173 is a deficient number, since it is larger than the sum of its proper divisors (18415).

78648173 is a wasteful number, since it uses less digits than its factorization.

78648173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18414.

The product of its digits is 225792, while the sum is 44.

The square root of 78648173 is about 8868.3805173211. The cubic root of 78648173 is about 428.4461185970.

The spelling of 78648173 in words is "seventy-eight million, six hundred forty-eight thousand, one hundred seventy-three".