30091221 has 6 divisors (see below), whose sum is σ = 43465110. Its totient is φ = 20060808.

The previous prime is 30091211. The next prime is 30091223. The reversal of 30091221 is 12219003.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 21762225 + 8328996 = 4665^2 + 2886^2 .

It is not a de Polignac number, because 30091221 - 2⁵ = 30091189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 30091194 and 30091203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30091223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1671726 + ... + 1671743.

It is an arithmetic number, because the mean of its divisors is an integer number (7244185).

Almost surely, 2^30091221 is an apocalyptic number.

It is an amenable number.

30091221 is a deficient number, since it is larger than the sum of its proper divisors (13373889).

30091221 is a wasteful number, since it uses less digits than its factorization.

30091221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3343475 (or 3343472 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 30091221 is about 5485.5465543554. The cubic root of 30091221 is about 311.0378706515.

The spelling of 30091221 in words is "thirty million, ninety-one thousand, two hundred twenty-one".