30821409 has 24 divisors (see below), whose sum is σ = 46735104. Its totient is φ = 19548000.

The previous prime is 30821393. The next prime is 30821429. The reversal of 30821409 is 90412803.

It is not a de Polignac number, because 30821409 - 2⁴ = 30821393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (30821429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16114 + ... + 17924.

It is an arithmetic number, because the mean of its divisors is an integer number (1947296).

Almost surely, 2^30821409 is an apocalyptic number.

It is an amenable number.

30821409 is a deficient number, since it is larger than the sum of its proper divisors (15913695).

30821409 is a wasteful number, since it uses less digits than its factorization.

30821409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1909 (or 1906 counting only the distinct ones).

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

The square root of 30821409 is about 5551.7032521560. The cubic root of 30821409 is about 313.5336532785.

The spelling of 30821409 in words is "thirty million, eight hundred twenty-one thousand, four hundred nine".