31230020 has 48 divisors (see below), whose sum is σ = 71705088. Its totient is φ = 11374080.

The previous prime is 31229999. The next prime is 31230029. The reversal of 31230020 is 2003213.

It is a junction number, because it is equal to n+sod(n) for n = 31229983 and 31230010.

It is not an unprimeable number, because it can be changed into a prime (31230029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9059 + ... + 12021.

It is an arithmetic number, because the mean of its divisors is an integer number (1493856).

Almost surely, 2^31230020 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 31230020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35852544).

31230020 is an abundant number, since it is smaller than the sum of its proper divisors (40475068).

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

31230020 is a wasteful number, since it uses less digits than its factorization.

31230020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3020 (or 3018 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 11.

The square root of 31230020 is about 5588.3825924860. The cubic root of 31230020 is about 314.9131195687.

Adding to 31230020 its reverse (2003213), we get a palindrome (33233233).

The spelling of 31230020 in words is "thirty-one million, two hundred thirty thousand, twenty".