78906641 has 6 divisors (see below), whose sum is σ = 86732226. Its totient is φ = 71733200.

The previous prime is 78906623. The next prime is 78906647. The reversal of 78906641 is 14660987.

It can be written as a sum of positive squares in only one way, i.e., 78411025 + 495616 = 8855^2 + 704^2 .

It is a de Polignac number, because none of the positive numbers 2^k-78906641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78906647) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 325940 + ... + 326181.

It is an arithmetic number, because the mean of its divisors is an integer number (14455371).

Almost surely, 2^78906641 is an apocalyptic number.

It is an amenable number.

78906641 is a deficient number, since it is larger than the sum of its proper divisors (7825585).

78906641 is a wasteful number, since it uses less digits than its factorization.

78906641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 652143 (or 652132 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 78906641 is about 8882.9410107239. The cubic root of 78906641 is about 428.9149513630.

The spelling of 78906641 in words is "seventy-eight million, nine hundred six thousand, six hundred forty-one".