30506021 has 24 divisors (see below), whose sum is σ = 38263104. Its totient is φ = 23811840.

The previous prime is 30506017. The next prime is 30506023. The reversal of 30506021 is 12060503.

It is not a de Polignac number, because 30506021 - 2² = 30506017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30506023) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 126461 + ... + 126701.

It is an arithmetic number, because the mean of its divisors is an integer number (1594296).

Almost surely, 2^30506021 is an apocalyptic number.

It is an amenable number.

30506021 is a deficient number, since it is larger than the sum of its proper divisors (7757083).

30506021 is a wasteful number, since it uses less digits than its factorization.

30506021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381 (or 368 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 30506021 is about 5523.2255974204. The cubic root of 30506021 is about 312.4605466992.

Adding to 30506021 its reverse (12060503), we get a palindrome (42566524).

The spelling of 30506021 in words is "thirty million, five hundred six thousand, twenty-one".