31321012121 has 12 divisors (see below), whose sum is σ = 36454206132. Its totient is φ = 26832169728.

The previous prime is 31321012103. The next prime is 31321012123. The reversal of 31321012121 is 12121012313.

It can be written as a sum of positive squares in 2 ways, for example, as 4371193225 + 26949818896 = 66115^2 + 164164^2 .

It is not a de Polignac number, because 31321012121 - 2¹⁴ = 31320995737 is a prime.

It is a super-3 number, since 3×31321012121³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31321012121.

It is not an unprimeable number, because it can be changed into a prime (31321012123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 78860 + ... + 262413.

It is an arithmetic number, because the mean of its divisors is an integer number (3037850511).

Almost surely, 2^31321012121 is an apocalyptic number.

It is an amenable number.

31321012121 is a deficient number, since it is larger than the sum of its proper divisors (5133194011).

31321012121 is a wasteful number, since it uses less digits than its factorization.

31321012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343160 (or 343153 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 31321012121 its reverse (12121012313), we get a palindrome (43442024434).

The spelling of 31321012121 in words is "thirty-one billion, three hundred twenty-one million, twelve thousand, one hundred twenty-one".