31220211121 has 16 divisors (see below), whose sum is σ = 34462065600. Its totient is φ = 28046022400.

The previous prime is 31220211107. The next prime is 31220211163. The reversal of 31220211121 is 12111202213.

It is not a de Polignac number, because 31220211121 - 2¹¹ = 31220209073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31220211095 and 31220211104.

It is not an unprimeable number, because it can be changed into a prime (31220211521) 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, 1764165 + ... + 1781773.

It is an arithmetic number, because the mean of its divisors is an integer number (2153879100).

Almost surely, 2^31220211121 is an apocalyptic number.

It is an amenable number.

31220211121 is a deficient number, since it is larger than the sum of its proper divisors (3241854479).

31220211121 is a wasteful number, since it uses less digits than its factorization.

31220211121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19520.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 31220211121 its reverse (12111202213), we get a palindrome (43331413334).

It can be divided in two parts, 312202 and 11121, that added together give a palindrome (323323).

The spelling of 31220211121 in words is "thirty-one billion, two hundred twenty million, two hundred eleven thousand, one hundred twenty-one".