31121230206 has 64 divisors (see below), whose sum is σ = 69801232896. Its totient is φ = 9170380800.

The previous prime is 31121230193. The next prime is 31121230207. The reversal of 31121230206 is 60203212113.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31121230207) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 296590 + ... + 387566.

It is an arithmetic number, because the mean of its divisors is an integer number (1090644264).

Almost surely, 2^31121230206 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31121230206, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34900616448).

31121230206 is an abundant number, since it is smaller than the sum of its proper divisors (38680002690).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31121230206 is a wasteful number, since it uses less digits than its factorization.

31121230206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91137.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 31121230206 its reverse (60203212113), we get a palindrome (91324442319).

The spelling of 31121230206 in words is "thirty-one billion, one hundred twenty-one million, two hundred thirty thousand, two hundred six".