71565979 has 2 divisors, whose sum is σ = 71565980. Its totient is φ = 71565978.

The previous prime is 71565973. The next prime is 71566009. The reversal of 71565979 is 97956517.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 71565979 - 2⁵ = 71565947 is a prime.

It is not a weakly prime, because it can be changed into another prime (71565973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35782989 + 35782990.

It is an arithmetic number, because the mean of its divisors is an integer number (35782990).

Almost surely, 2^71565979 is an apocalyptic number.

71565979 is a deficient number, since it is larger than the sum of its proper divisors (1).

71565979 is an equidigital number, since it uses as much as digits as its factorization.

71565979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 595350, while the sum is 49.

The square root of 71565979 is about 8459.6677830752. The cubic root of 71565979 is about 415.1791533069.

The spelling of 71565979 in words is "seventy-one million, five hundred sixty-five thousand, nine hundred seventy-nine".