30281920 has 56 divisors (see below), whose sum is σ = 72658224. Its totient is φ = 12020736.

The previous prime is 30281899. The next prime is 30281941. The reversal of 30281920 is 2918203.

It is an interprime number because it is at equal distance from previous prime (30281899) and next prime (30281941).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55087 + ... + 55633.

Almost surely, 2^30281920 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 30281920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36329112).

30281920 is an abundant number, since it is smaller than the sum of its proper divisors (42376304).

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

30281920 is a wasteful number, since it uses less digits than its factorization.

30281920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737 (or 727 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 30281920 is about 5502.9010530810. The cubic root of 30281920 is about 311.6935408526.

The spelling of 30281920 in words is "thirty million, two hundred eighty-one thousand, nine hundred twenty".