71891087 has 8 divisors (see below), whose sum is σ = 75632400. Its totient is φ = 68233984.

The previous prime is 71891051. The next prime is 71891101. The reversal of 71891087 is 78019817.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 71891087 - 2⁸ = 71890831 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71891047) 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 in 7 ways as a sum of consecutive naturals, for example, 19298 + ... + 22719.

It is an arithmetic number, because the mean of its divisors is an integer number (9454050).

Almost surely, 2^71891087 is an apocalyptic number.

71891087 is a deficient number, since it is larger than the sum of its proper divisors (3741313).

71891087 is a wasteful number, since it uses less digits than its factorization.

71891087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42105.

The product of its (nonzero) digits is 28224, while the sum is 41.

The square root of 71891087 is about 8478.8611853244. The cubic root of 71891087 is about 415.8068919278.

The spelling of 71891087 in words is "seventy-one million, eight hundred ninety-one thousand, eighty-seven".