31302212220 has 144 divisors (see below), whose sum is σ = 96777993312. Its totient is φ = 8187333120.

The previous prime is 31302212209. The next prime is 31302212261. The reversal of 31302212220 is 2221220313.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 31302212193 and 31302212202.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 4091719 + ... + 4099361.

It is an arithmetic number, because the mean of its divisors is an integer number (672069398).

Almost surely, 2^31302212220 is an apocalyptic number.

31302212220 is a gapful number since it is divisible by the number (30) 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 31302212220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48388996656).

31302212220 is an abundant number, since it is smaller than the sum of its proper divisors (65475781092).

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

31302212220 is a wasteful number, since it uses less digits than its factorization.

31302212220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8092 (or 8087 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 31302212220 its reverse (2221220313), we get a palindrome (33523432533).

The spelling of 31302212220 in words is "thirty-one billion, three hundred two million, two hundred twelve thousand, two hundred twenty".