78644461 has 12 divisors (see below), whose sum is σ = 91716192. Its totient is φ = 67238808.

The previous prime is 78644453. The next prime is 78644483. The reversal of 78644461 is 16444687.

It is not a de Polignac number, because 78644461 - 2³ = 78644453 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 (78644161) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 19896 + ... + 23518.

It is an arithmetic number, because the mean of its divisors is an integer number (7643016).

Almost surely, 2^78644461 is an apocalyptic number.

It is an amenable number.

78644461 is a deficient number, since it is larger than the sum of its proper divisors (13071731).

78644461 is a wasteful number, since it uses less digits than its factorization.

78644461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4080 (or 4073 counting only the distinct ones).

The product of its digits is 129024, while the sum is 40.

The square root of 78644461 is about 8868.1712319959. The cubic root of 78644461 is about 428.4393779572.

It can be divided in two parts, 7 and 8644461, that added together give a palindrome (8644468).

The spelling of 78644461 in words is "seventy-eight million, six hundred forty-four thousand, four hundred sixty-one".