30709221 has 4 divisors (see below), whose sum is σ = 40945632. Its totient is φ = 20472812.

The previous prime is 30709201. The next prime is 30709229. The reversal of 30709221 is 12290703.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 30709221 - 2⁷ = 30709093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 30709191 and 30709200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30709229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5118201 + ... + 5118206.

It is an arithmetic number, because the mean of its divisors is an integer number (10236408).

Almost surely, 2^30709221 is an apocalyptic number.

It is an amenable number.

30709221 is a deficient number, since it is larger than the sum of its proper divisors (10236411).

30709221 is a wasteful number, since it uses less digits than its factorization.

30709221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10236410.

The product of its (nonzero) digits is 756, while the sum is 24.

The square root of 30709221 is about 5541.5901147595. The cubic root of 30709221 is about 313.1527764890.

Adding to 30709221 its reverse (12290703), we get a palindrome (42999924).

The spelling of 30709221 in words is "thirty million, seven hundred nine thousand, two hundred twenty-one".