31200030 has 24 divisors (see below), whose sum is σ = 81120312. Its totient is φ = 8319984.

The previous prime is 31200007. The next prime is 31200061. The reversal of 31200030 is 3000213.

31200030 = 2496² + 2497² + ... + 2500².

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 31199985 and 31200021.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 173244 + ... + 173423.

It is an arithmetic number, because the mean of its divisors is an integer number (3380013).

Almost surely, 2^31200030 is an apocalyptic number.

31200030 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31200030 is an abundant number, since it is smaller than the sum of its proper divisors (49920282).

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

31200030 is a wasteful number, since it uses less digits than its factorization.

31200030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346680 (or 346677 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 9.

The square root of 31200030 is about 5585.6987029377. The cubic root of 31200030 is about 314.8122842276.

Adding to 31200030 its reverse (3000213), we get a palindrome (34200243).

The spelling of 31200030 in words is "thirty-one million, two hundred thousand, thirty".