221021030231 has 4 divisors (see below), whose sum is σ = 222504393000. Its totient is φ = 219537667464.

The previous prime is 221021030227. The next prime is 221021030303. The reversal of 221021030231 is 132030120122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221021030231 - 2² = 221021030227 is a prime.

It is a super-2 number, since 2×221021030231² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021030831) 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, 741681161 + ... + 741681458.

It is an arithmetic number, because the mean of its divisors is an integer number (55626098250).

Almost surely, 2^221021030231 is an apocalyptic number.

221021030231 is a deficient number, since it is larger than the sum of its proper divisors (1483362769).

221021030231 is a wasteful number, since it uses less digits than its factorization.

221021030231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1483362768.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 221021030231 its reverse (132030120122), we get a palindrome (353051150353).

The spelling of 221021030231 in words is "two hundred twenty-one billion, twenty-one million, thirty thousand, two hundred thirty-one".