31420224 has 280 divisors, whose sum is σ = 110642400. Its totient is φ = 8709120.

The previous prime is 31420223. The next prime is 31420303. The reversal of 31420224 is 42202413.

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

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 31420197 and 31420206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31420223) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1083442 + ... + 1083470.

Almost surely, 2^31420224 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 31420224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55321200).

31420224 is an abundant number, since it is smaller than the sum of its proper divisors (79222176).

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

31420224 is a wasteful number, since it uses less digits than its factorization.

31420224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 31420224 is about 5605.3745637558. The cubic root of 31420224 is about 315.5511439647.

Adding to 31420224 its reverse (42202413), we get a palindrome (73622637).

The spelling of 31420224 in words is "thirty-one million, four hundred twenty thousand, two hundred twenty-four".