221209500231 has 16 divisors (see below), whose sum is σ = 346995295200. Its totient is φ = 138798117504.

The previous prime is 221209500221. The next prime is 221209500233. The reversal of 221209500231 is 132005902122.

It is a happy number.

221209500231 is a `hidden beast` number, since 2 + 2 + 120 + 9 + 500 + 2 + 31 = 666.

It is not a de Polignac number, because 221209500231 - 2¹⁷ = 221209369159 is a prime.

It is a super-2 number, since 2×221209500231² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 221209500195 and 221209500204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221209500233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 240968496 + ... + 240969413.

It is an arithmetic number, because the mean of its divisors is an integer number (21687205950).

Almost surely, 2^221209500231 is an apocalyptic number.

221209500231 is a deficient number, since it is larger than the sum of its proper divisors (125785794969).

221209500231 is a wasteful number, since it uses less digits than its factorization.

221209500231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481937935 (or 481937929 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The spelling of 221209500231 in words is "two hundred twenty-one billion, two hundred nine million, five hundred thousand, two hundred thirty-one".