71547979 has 2 divisors, whose sum is σ = 71547980. Its totient is φ = 71547978.

The previous prime is 71547961. The next prime is 71547991. The reversal of 71547979 is 97974517.

It is a strong prime.

It is an emirp because it is prime and its reverse (97974517) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71547979 - 2⁵ = 71547947 is a prime.

It is a super-2 number, since 2×71547979² = 10238226597968882, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71547919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35773989 + 35773990.

It is an arithmetic number, because the mean of its divisors is an integer number (35773990).

Almost surely, 2^71547979 is an apocalyptic number.

71547979 is a deficient number, since it is larger than the sum of its proper divisors (1).

71547979 is an equidigital number, since it uses as much as digits as its factorization.

71547979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 555660, while the sum is 49.

The square root of 71547979 is about 8458.6038446070. The cubic root of 71547979 is about 415.1443422999.

The spelling of 71547979 in words is "seventy-one million, five hundred forty-seven thousand, nine hundred seventy-nine".