30722721 has 4 divisors (see below), whose sum is σ = 40963632. Its totient is φ = 20481812.

The previous prime is 30722719. The next prime is 30722743. The reversal of 30722721 is 12722703.

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 30722721 - 2¹ = 30722719 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 30722691 and 30722700.

It is not an unprimeable number, because it can be changed into a prime (30722701) 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, 5120451 + ... + 5120456.

It is an arithmetic number, because the mean of its divisors is an integer number (10240908).

Almost surely, 2^30722721 is an apocalyptic number.

It is an amenable number.

30722721 is a deficient number, since it is larger than the sum of its proper divisors (10240911).

30722721 is a wasteful number, since it uses less digits than its factorization.

30722721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10240910.

The product of its (nonzero) digits is 1176, while the sum is 24.

The square root of 30722721 is about 5542.8080428606. The cubic root of 30722721 is about 313.1986578563.

The spelling of 30722721 in words is "thirty million, seven hundred twenty-two thousand, seven hundred twenty-one".