30391220 has 12 divisors (see below), whose sum is σ = 63821604. Its totient is φ = 12156480.

The previous prime is 30391219. The next prime is 30391243. The reversal of 30391220 is 2219303.

It can be written as a sum of positive squares in 2 ways, for example, as 13118884 + 17272336 = 3622^2 + 4156^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1519561 = 30391220 / (3 + 0 + 3 + 9 + 1 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 30391192 and 30391201.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 759761 + ... + 759800.

It is an arithmetic number, because the mean of its divisors is an integer number (5318467).

Almost surely, 2^30391220 is an apocalyptic number.

It is an amenable number.

30391220 is an abundant number, since it is smaller than the sum of its proper divisors (33430384).

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

30391220 is a wasteful number, since it uses less digits than its factorization.

30391220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1519570 (or 1519568 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 30391220 is about 5512.8232331538. The cubic root of 30391220 is about 312.0681009573.

The spelling of 30391220 in words is "thirty million, three hundred ninety-one thousand, two hundred twenty".