30161920 has 88 divisors (see below), whose sum is σ = 74576304. Its totient is φ = 11698176.

The previous prime is 30161881. The next prime is 30161941. The reversal of 30161920 is 2916103.

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 30161891 and 30161900.

It is a congruent number.

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, 220092 + ... + 220228.

It is an arithmetic number, because the mean of its divisors is an integer number (847458).

Almost surely, 2^30161920 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 30161920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37288152).

30161920 is an abundant number, since it is smaller than the sum of its proper divisors (44414384).

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

30161920 is a wasteful number, since it uses less digits than its factorization.

30161920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 30161920 is about 5491.9868900062. The cubic root of 30161920 is about 311.2812735037.

The spelling of 30161920 in words is "thirty million, one hundred sixty-one thousand, nine hundred twenty".