31102121221 has 8 divisors (see below), whose sum is σ = 31272998400. Its totient is φ = 30931328160.

The previous prime is 31102121213. The next prime is 31102121251. The reversal of 31102121221 is 12212120113.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31102121221 - 2³ = 31102121213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31102121195 and 31102121204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31102121251) 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 7 ways as a sum of consecutive naturals, for example, 809985 + ... + 847513.

It is an arithmetic number, because the mean of its divisors is an integer number (3909124800).

Almost surely, 2^31102121221 is an apocalyptic number.

It is an amenable number.

31102121221 is a deficient number, since it is larger than the sum of its proper divisors (170877179).

31102121221 is a wasteful number, since it uses less digits than its factorization.

31102121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42059.

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

Adding to 31102121221 its reverse (12212120113), we get a palindrome (43314241334).

The spelling of 31102121221 in words is "thirty-one billion, one hundred two million, one hundred twenty-one thousand, two hundred twenty-one".