30388905 has 32 divisors (see below), whose sum is σ = 54395520. Its totient is φ = 16096320.

The previous prime is 30388871. The next prime is 30388907. The reversal of 30388905 is 50988303.

It is not a de Polignac number, because 30388905 - 2⁷ = 30388777 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30388905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30388907) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21315 + ... + 22695.

It is an arithmetic number, because the mean of its divisors is an integer number (1699860).

Almost surely, 2^30388905 is an apocalyptic number.

It is an amenable number.

30388905 is a deficient number, since it is larger than the sum of its proper divisors (24006615).

30388905 is a wasteful number, since it uses less digits than its factorization.

30388905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1558 (or 1552 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 30388905 is about 5512.6132641425. The cubic root of 30388905 is about 312.0601770021.

The spelling of 30388905 in words is "thirty million, three hundred eighty-eight thousand, nine hundred five".