71221857 has 16 divisors (see below), whose sum is σ = 114913152. Its totient is φ = 38304000.

The previous prime is 71221853. The next prime is 71221903. The reversal of 71221857 is 75812217.

It is not a de Polignac number, because 71221857 - 2² = 71221853 is a prime.

It is not an unprimeable number, because it can be changed into a prime (71221853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99394 + ... + 100107.

It is an arithmetic number, because the mean of its divisors is an integer number (7182072).

Almost surely, 2^71221857 is an apocalyptic number.

It is an amenable number.

71221857 is a deficient number, since it is larger than the sum of its proper divisors (43691295).

71221857 is a wasteful number, since it uses less digits than its factorization.

71221857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199528.

The product of its digits is 7840, while the sum is 33.

The square root of 71221857 is about 8439.3042959713. The cubic root of 71221857 is about 414.5126266753.

The spelling of 71221857 in words is "seventy-one million, two hundred twenty-one thousand, eight hundred fifty-seven".