31424220 has 48 divisors (see below), whose sum is σ = 97765920. Its totient is φ = 8379648.

The previous prime is 31424207. The next prime is 31424221. The reversal of 31424220 is 2242413.

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 = 31424193 and 31424202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31424221) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 28557 + ... + 29636.

It is an arithmetic number, because the mean of its divisors is an integer number (2036790).

Almost surely, 2^31424220 is an apocalyptic number.

31424220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31424220 is an abundant number, since it is smaller than the sum of its proper divisors (66341700).

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

31424220 is a wasteful number, since it uses less digits than its factorization.

31424220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58211 (or 58203 counting only the distinct ones).

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

The square root of 31424220 is about 5605.7309960432. The cubic root of 31424220 is about 315.5645205818.

Adding to 31424220 its reverse (2242413), we get a palindrome (33666633).

The spelling of 31424220 in words is "thirty-one million, four hundred twenty-four thousand, two hundred twenty".