30641920 has 72 divisors (see below), whose sum is σ = 75497184. Its totient is φ = 11907072.

The previous prime is 30641917. The next prime is 30641921. The reversal of 30641920 is 2914603.

It is a super-2 number, since 2×30641920² = 1877854522572800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30641921) 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 7 ways as a sum of consecutive naturals, for example, 47037 + ... + 47683.

It is an arithmetic number, because the mean of its divisors is an integer number (1048572).

Almost surely, 2^30641920 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 30641920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37748592).

30641920 is an abundant number, since it is smaller than the sum of its proper divisors (44855264).

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

30641920 is an equidigital number, since it uses as much as digits as its factorization.

30641920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 705 (or 691 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 30641920 is about 5535.5144295720. The cubic root of 30641920 is about 312.9238451437.

The spelling of 30641920 in words is "thirty million, six hundred forty-one thousand, nine hundred twenty".