31304430 has 48 divisors (see below), whose sum is σ = 83294640. Its totient is φ = 8152704.

The previous prime is 31304423. The next prime is 31304437. The reversal of 31304430 is 3440313.

It is an interprime number because it is at equal distance from previous prime (31304423) and next prime (31304437).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31304437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 175 + ... + 7914.

It is an arithmetic number, because the mean of its divisors is an integer number (1735305).

Almost surely, 2^31304430 is an apocalyptic number.

31304430 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 31304430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41647320).

31304430 is an abundant number, since it is smaller than the sum of its proper divisors (51990210).

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

31304430 is a wasteful number, since it uses less digits than its factorization.

31304430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8145 (or 8142 counting only the distinct ones).

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

The square root of 31304430 is about 5595.0361929124. The cubic root of 31304430 is about 315.1630297432.

Adding to 31304430 its reverse (3440313), we get a palindrome (34744743).

The spelling of 31304430 in words is "thirty-one million, three hundred four thousand, four hundred thirty".