31211111421 has 24 divisors (see below), whose sum is σ = 52143873600. Its totient is φ = 17620039296.

The previous prime is 31211111419. The next prime is 31211111423. The reversal of 31211111421 is 12411111213.

31211111421 is a `hidden beast` number, since 31 + 211 + 1 + 1 + 1 + 421 = 666.

It is an interprime number because it is at equal distance from previous prime (31211111419) and next prime (31211111423).

It is not a de Polignac number, because 31211111421 - 2¹ = 31211111419 is a prime.

It is a super-2 number, since 2×31211111421² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31211111394 and 31211111403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31211111423) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2979196 + ... + 2989653.

It is an arithmetic number, because the mean of its divisors is an integer number (2172661400).

Almost surely, 2^31211111421 is an apocalyptic number.

It is an amenable number.

31211111421 is a deficient number, since it is larger than the sum of its proper divisors (20932762179).

31211111421 is a wasteful number, since it uses less digits than its factorization.

31211111421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5968945 (or 5968942 counting only the distinct ones).

The product of its digits is 48, while the sum is 18.

Adding to 31211111421 its reverse (12411111213), we get a palindrome (43622222634).

The spelling of 31211111421 in words is "thirty-one billion, two hundred eleven million, one hundred eleven thousand, four hundred twenty-one".