71221201211 has 4 divisors (see below), whose sum is σ = 71699196000. Its totient is φ = 70743206424.

The previous prime is 71221201169. The next prime is 71221201213. The reversal of 71221201211 is 11210212217.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 71221201211 - 2¹⁰ = 71221200187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71221201213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 238997171 + ... + 238997468.

It is an arithmetic number, because the mean of its divisors is an integer number (17924799000).

Almost surely, 2^71221201211 is an apocalyptic number.

71221201211 is a deficient number, since it is larger than the sum of its proper divisors (477994789).

71221201211 is a wasteful number, since it uses less digits than its factorization.

71221201211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477994788.

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 71221201211 its reverse (11210212217), we get a palindrome (82431413428).

The spelling of 71221201211 in words is "seventy-one billion, two hundred twenty-one million, two hundred one thousand, two hundred eleven".