31223430 has 96 divisors (see below), whose sum is σ = 96033600. Its totient is φ = 6886656.

The previous prime is 31223429. The next prime is 31223471. The reversal of 31223430 is 3432213.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17416 + ... + 19124.

It is an arithmetic number, because the mean of its divisors is an integer number (1000350).

Almost surely, 2^31223430 is an apocalyptic number.

31223430 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 31223430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48016800).

31223430 is an abundant number, since it is smaller than the sum of its proper divisors (64810170).

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

31223430 is a wasteful number, since it uses less digits than its factorization.

31223430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1758 (or 1755 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

The square root of 31223430 is about 5587.7929453408. The cubic root of 31223430 is about 314.8909675554.

Adding to 31223430 its reverse (3432213), we get a palindrome (34655643).

The spelling of 31223430 in words is "thirty-one million, two hundred twenty-three thousand, four hundred thirty".