78724571 has 2 divisors, whose sum is σ = 78724572. Its totient is φ = 78724570.

The previous prime is 78724559. The next prime is 78724573. The reversal of 78724571 is 17542787.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78724571 - 2¹⁴ = 78708187 is a prime.

Together with 78724573, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78724573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39362285 + 39362286.

It is an arithmetic number, because the mean of its divisors is an integer number (39362286).

Almost surely, 2^78724571 is an apocalyptic number.

78724571 is a deficient number, since it is larger than the sum of its proper divisors (1).

78724571 is an equidigital number, since it uses as much as digits as its factorization.

78724571 is an evil number, because the sum of its binary digits is even.

The product of its digits is 109760, while the sum is 41.

The square root of 78724571 is about 8872.6867971320. The cubic root of 78724571 is about 428.5848030376.

The spelling of 78724571 in words is "seventy-eight million, seven hundred twenty-four thousand, five hundred seventy-one".