71905091 has 2 divisors, whose sum is σ = 71905092. Its totient is φ = 71905090.

The previous prime is 71905081. The next prime is 71905109. The reversal of 71905091 is 19050917.

Together with next prime (71905109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is an emirp because it is prime and its reverse (19050917) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71905091 - 2²² = 67710787 is a prime.

It is a super-2 number, since 2×71905091² = 10340684223436562, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71905051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35952545 + 35952546.

It is an arithmetic number, because the mean of its divisors is an integer number (35952546).

Almost surely, 2^71905091 is an apocalyptic number.

71905091 is a deficient number, since it is larger than the sum of its proper divisors (1).

71905091 is an equidigital number, since it uses as much as digits as its factorization.

71905091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2835, while the sum is 32.

The square root of 71905091 is about 8479.6869635618. The cubic root of 71905091 is about 415.8338891626.

The spelling of 71905091 in words is "seventy-one million, nine hundred five thousand, ninety-one".