31212223232 has 72 divisors (see below), whose sum is σ = 66395137536. Its totient is φ = 14609847296.

The previous prime is 31212223183. The next prime is 31212223249. The reversal of 31212223232 is 23232221213.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a junction number, because it is equal to n+sod(n) for n = 31212223198 and 31212223207.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220343 + ... + 333129.

It is an arithmetic number, because the mean of its divisors is an integer number (922154688).

Almost surely, 2^31212223232 is an apocalyptic number.

31212223232 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31212223232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33197568768).

31212223232 is an abundant number, since it is smaller than the sum of its proper divisors (35182914304).

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

31212223232 is a wasteful number, since it uses less digits than its factorization.

31212223232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112873 (or 112859 counting only the distinct ones).

The product of its digits is 1728, while the sum is 23.

Adding to 31212223232 its reverse (23232221213), we get a palindrome (54444444445).

The spelling of 31212223232 in words is "thirty-one billion, two hundred twelve million, two hundred twenty-three thousand, two hundred thirty-two".