30506240 has 36 divisors (see below), whose sum is σ = 73075044. Its totient is φ = 12201984.

The previous prime is 30506237. The next prime is 30506249. The reversal of 30506240 is 4260503.

It can be written as a sum of positive squares in 2 ways, for example, as 19642624 + 10863616 = 4432^2 + 3296^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30506249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10637 + ... + 13196.

Almost surely, 2^30506240 is an apocalyptic number.

It is an amenable number.

30506240 is an abundant number, since it is smaller than the sum of its proper divisors (42568804).

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

30506240 is an equidigital number, since it uses as much as digits as its factorization.

30506240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23854 (or 23840 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 30506240 is about 5523.2454227564. The cubic root of 30506240 is about 312.4612944062.

Adding to 30506240 its reverse (4260503), we get a palindrome (34766743).

The spelling of 30506240 in words is "thirty million, five hundred six thousand, two hundred forty".