78520571 has 2 divisors, whose sum is σ = 78520572. Its totient is φ = 78520570.

The previous prime is 78520553. The next prime is 78520601. The reversal of 78520571 is 17502587.

It is a weak prime.

It is an emirp because it is prime and its reverse (17502587) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78520571 - 2¹⁴ = 78504187 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78520511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39260285 + 39260286.

It is an arithmetic number, because the mean of its divisors is an integer number (39260286).

Almost surely, 2^78520571 is an apocalyptic number.

78520571 is a deficient number, since it is larger than the sum of its proper divisors (1).

78520571 is an equidigital number, since it uses as much as digits as its factorization.

78520571 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19600, while the sum is 35.

The square root of 78520571 is about 8861.1833859818. The cubic root of 78520571 is about 428.2142836931.

The spelling of 78520571 in words is "seventy-eight million, five hundred twenty thousand, five hundred seventy-one".