30905280 has 336 divisors, whose sum is σ = 128564640. Its totient is φ = 6967296.

The previous prime is 30905279. The next prime is 30905311. The reversal of 30905280 is 8250903.

It is a tau number, because it is divible by the number of its divisors (336).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 423324 + ... + 423396.

Almost surely, 2^30905280 is an apocalyptic number.

30905280 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30905280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64282320).

30905280 is an abundant number, since it is smaller than the sum of its proper divisors (97659360).

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

30905280 is a wasteful number, since it uses less digits than its factorization.

30905280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 30905280 is about 5559.2517482122. The cubic root of 30905280 is about 313.8177908891.

The spelling of 30905280 in words is "thirty million, nine hundred five thousand, two hundred eighty".