31430320 has 20 divisors (see below), whose sum is σ = 73075680. Its totient is φ = 12572096.

The previous prime is 31430293. The next prime is 31430323. The reversal of 31430320 is 2303413.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 31430294 and 31430303.

It is not an unprimeable number, because it can be changed into a prime (31430323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196360 + ... + 196519.

It is an arithmetic number, because the mean of its divisors is an integer number (3653784).

Almost surely, 2^31430320 is an apocalyptic number.

It is an amenable number.

31430320 is an abundant number, since it is smaller than the sum of its proper divisors (41645360).

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

31430320 is a wasteful number, since it uses less digits than its factorization.

31430320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392892 (or 392886 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 16.

The square root of 31430320 is about 5606.2750556854. The cubic root of 31430320 is about 315.5849381561.

Adding to 31430320 its reverse (2303413), we get a palindrome (33733733).

The spelling of 31430320 in words is "thirty-one million, four hundred thirty thousand, three hundred twenty".