231121320209 has 16 divisors (see below), whose sum is σ = 277411639680. Its totient is φ = 190225117440.

The previous prime is 231121320091. The next prime is 231121320223. The reversal of 231121320209 is 902023121132.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231121320209 is a prime.

It is a super-2 number, since 2×231121320209² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231121320299) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27516797 + ... + 27525194.

It is an arithmetic number, because the mean of its divisors is an integer number (17338227480).

Almost surely, 2^231121320209 is an apocalyptic number.

It is an amenable number.

231121320209 is a deficient number, since it is larger than the sum of its proper divisors (46290319471).

231121320209 is a wasteful number, since it uses less digits than its factorization.

231121320209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55042040.

The product of its (nonzero) digits is 1296, while the sum is 26.

The spelling of 231121320209 in words is "two hundred thirty-one billion, one hundred twenty-one million, three hundred twenty thousand, two hundred nine".