78744791 has 2 divisors, whose sum is σ = 78744792. Its totient is φ = 78744790.

The previous prime is 78744781. The next prime is 78744817. The reversal of 78744791 is 19744787.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78744791 - 2¹⁴ = 78728407 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78744781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39372395 + 39372396.

It is an arithmetic number, because the mean of its divisors is an integer number (39372396).

Almost surely, 2^78744791 is an apocalyptic number.

78744791 is a deficient number, since it is larger than the sum of its proper divisors (1).

78744791 is an equidigital number, since it uses as much as digits as its factorization.

78744791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 395136, while the sum is 47.

The square root of 78744791 is about 8873.8261758950. The cubic root of 78744791 is about 428.6214931619.

The spelling of 78744791 in words is "seventy-eight million, seven hundred forty-four thousand, seven hundred ninety-one".