31530000 has 100 divisors (see below), whose sum is σ = 101879888. Its totient is φ = 8400000.

The previous prime is 31529977. The next prime is 31530001. The reversal of 31530000 is 3513.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (100).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (31530001) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 29475 + ... + 30525.

Almost surely, 2^31530000 is an apocalyptic number.

31530000 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31530000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50939944).

31530000 is an abundant number, since it is smaller than the sum of its proper divisors (70349888).

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

31530000 is a wasteful number, since it uses less digits than its factorization.

31530000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1082 (or 1061 counting only the distinct ones).

The product of its (nonzero) digits is 45, while the sum is 12.

The square root of 31530000 is about 5615.1580565466. The cubic root of 31530000 is about 315.9182077473.

Adding to 31530000 its reverse (3513), we get a palindrome (31533513).

The spelling of 31530000 in words is "thirty-one million, five hundred thirty thousand".