30121216 has 36 divisors (see below), whose sum is σ = 60794692. Its totient is φ = 14893056.

The previous prime is 30121207. The next prime is 30121241. The reversal of 30121216 is 61212103.

It can be written as a sum of positive squares in 2 ways, for example, as 6150400 + 23970816 = 2480^2 + 4896^2 .

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

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 30121216.

It is a congruent number.

It is an unprimeable number.

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, 24226 + ... + 25438.

Almost surely, 2^30121216 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 30121216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30397346).

30121216 is an abundant number, since it is smaller than the sum of its proper divisors (30673476).

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

30121216 is an equidigital number, since it uses as much as digits as its factorization.

30121216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1326 (or 1312 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 30121216 is about 5488.2798762454. The cubic root of 30121216 is about 311.1411840922.

Adding to 30121216 its reverse (61212103), we get a palindrome (91333319).

The spelling of 30121216 in words is "thirty million, one hundred twenty-one thousand, two hundred sixteen".