30215920 has 80 divisors (see below), whose sum is σ = 81423360. Its totient is φ = 10213632.

The previous prime is 30215891. The next prime is 30215921. The reversal of 30215920 is 2951203.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 30215891 and 30215900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30215921) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 43899 + ... + 44581.

It is an arithmetic number, because the mean of its divisors is an integer number (1017792).

Almost surely, 2^30215920 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 30215920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40711680).

30215920 is an abundant number, since it is smaller than the sum of its proper divisors (51207440).

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

30215920 is a wasteful number, since it uses less digits than its factorization.

30215920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 782 (or 776 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 30215920 is about 5496.9009450781. The cubic root of 30215920 is about 311.4669288749.

The spelling of 30215920 in words is "thirty million, two hundred fifteen thousand, nine hundred twenty".