78751919 has 2 divisors, whose sum is σ = 78751920. Its totient is φ = 78751918.

The previous prime is 78751901. The next prime is 78751987. The reversal of 78751919 is 91915787.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78751919 - 2²⁰ = 77703343 is a prime.

It is a super-2 number, since 2×78751919² = 12403729492365122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78751999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39375959 + 39375960.

It is an arithmetic number, because the mean of its divisors is an integer number (39375960).

Almost surely, 2^78751919 is an apocalyptic number.

78751919 is a deficient number, since it is larger than the sum of its proper divisors (1).

78751919 is an equidigital number, since it uses as much as digits as its factorization.

78751919 is an evil number, because the sum of its binary digits is even.

The product of its digits is 158760, while the sum is 47.

The square root of 78751919 is about 8874.2277973917. The cubic root of 78751919 is about 428.6344257500.

The spelling of 78751919 in words is "seventy-eight million, seven hundred fifty-one thousand, nine hundred nineteen".