31223212400 has 120 divisors (see below), whose sum is σ = 77630471808. Its totient is φ = 12055680000.

The previous prime is 31223212399. The next prime is 31223212403. The reversal of 31223212400 is 421232213.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31223212403) 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, 5217410 + ... + 5223390.

Almost surely, 2^31223212400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31223212400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38815235904).

31223212400 is an abundant number, since it is smaller than the sum of its proper divisors (46407259408).

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

31223212400 is a wasteful number, since it uses less digits than its factorization.

31223212400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6451 (or 6440 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 31223212400 its reverse (421232213), we get a palindrome (31644444613).

The spelling of 31223212400 in words is "thirty-one billion, two hundred twenty-three million, two hundred twelve thousand, four hundred".