78651841 has 4 divisors (see below), whose sum is σ = 80135892. Its totient is φ = 77167792.

The previous prime is 78651827. The next prime is 78651863. The reversal of 78651841 is 14815687.

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 68823616 + 9828225 = 8296^2 + 3135^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78651841 is a prime.

It is a super-2 number, since 2×78651841² = 12372224185378562, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78651794 and 78651803.

It is not an unprimeable number, because it can be changed into a prime (78651871) 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, 741946 + ... + 742051.

It is an arithmetic number, because the mean of its divisors is an integer number (20033973).

Almost surely, 2^78651841 is an apocalyptic number.

It is an amenable number.

78651841 is a deficient number, since it is larger than the sum of its proper divisors (1484051).

78651841 is a wasteful number, since it uses less digits than its factorization.

78651841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1484050.

The product of its digits is 53760, while the sum is 40.

The square root of 78651841 is about 8868.5873170421. The cubic root of 78651841 is about 428.4527791286.

The spelling of 78651841 in words is "seventy-eight million, six hundred fifty-one thousand, eight hundred forty-one".