78746645 has 4 divisors (see below), whose sum is σ = 94495980. Its totient is φ = 62997312.

The previous prime is 78746639. The next prime is 78746653. The reversal of 78746645 is 54664787.

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 12909649 + 65836996 = 3593^2 + 8114^2 .

It is a cyclic number.

It is not a de Polignac number, because 78746645 - 2²⁶ = 11637781 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 78746645.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7874660 + ... + 7874669.

It is an arithmetic number, because the mean of its divisors is an integer number (23623995).

Almost surely, 2^78746645 is an apocalyptic number.

It is an amenable number.

78746645 is a deficient number, since it is larger than the sum of its proper divisors (15749335).

78746645 is a wasteful number, since it uses less digits than its factorization.

78746645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15749334.

The product of its digits is 1128960, while the sum is 47.

The square root of 78746645 is about 8873.9306398011. The cubic root of 78746645 is about 428.6248570162.

The spelling of 78746645 in words is "seventy-eight million, seven hundred forty-six thousand, six hundred forty-five".