78961104689 has 2 divisors, whose sum is σ = 78961104690. Its totient is φ = 78961104688.

The previous prime is 78961104667. The next prime is 78961104709. The reversal of 78961104689 is 98640116987.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47288851600 + 31672253089 = 217460^2 + 177967^2 .

It is a cyclic number.

It is not a de Polignac number, because 78961104689 - 2²⁸ = 78692669233 is a prime.

It is a super-3 number, since 3×78961104689³ (a number of 34 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (78961104389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39480552344 + 39480552345.

It is an arithmetic number, because the mean of its divisors is an integer number (39480552345).

Almost surely, 2^78961104689 is an apocalyptic number.

It is an amenable number.

78961104689 is a deficient number, since it is larger than the sum of its proper divisors (1).

78961104689 is an equidigital number, since it uses as much as digits as its factorization.

78961104689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5225472, while the sum is 59.

The spelling of 78961104689 in words is "seventy-eight billion, nine hundred sixty-one million, one hundred four thousand, six hundred eighty-nine".