30408921 has 24 divisors (see below), whose sum is σ = 46964736. Its totient is φ = 18912960.

The previous prime is 30408913. The next prime is 30408941. The reversal of 30408921 is 12980403.

It is not a de Polignac number, because 30408921 - 2³ = 30408913 is a prime.

It is not an unprimeable number, because it can be changed into a prime (30408941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6696 + ... + 10278.

It is an arithmetic number, because the mean of its divisors is an integer number (1956864).

Almost surely, 2^30408921 is an apocalyptic number.

It is an amenable number.

30408921 is a deficient number, since it is larger than the sum of its proper divisors (16555815).

30408921 is a wasteful number, since it uses less digits than its factorization.

30408921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3653 (or 3650 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 30408921 is about 5514.4284381974. The cubic root of 30408921 is about 312.1286759672.

It can be divided in two parts, 30408 and 921, that added together give a square (31329 = 177²).

The spelling of 30408921 in words is "thirty million, four hundred eight thousand, nine hundred twenty-one".