30807921 has 8 divisors (see below), whose sum is σ = 41140960. Its totient is φ = 20506752.

The previous prime is 30807919. The next prime is 30807937. The reversal of 30807921 is 12970803.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 30807921 - 2¹ = 30807919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30807901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5611 + ... + 9648.

It is an arithmetic number, because the mean of its divisors is an integer number (5142620).

Almost surely, 2^30807921 is an apocalyptic number.

It is an amenable number.

30807921 is a deficient number, since it is larger than the sum of its proper divisors (10333039).

30807921 is a wasteful number, since it uses less digits than its factorization.

30807921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15935.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 30807921 is about 5550.4883568926. The cubic root of 30807921 is about 313.4879106266.

The spelling of 30807921 in words is "thirty million, eight hundred seven thousand, nine hundred twenty-one".