221201131 has 2 divisors, whose sum is σ = 221201132. Its totient is φ = 221201130.

The previous prime is 221201117. The next prime is 221201137. The reversal of 221201131 is 131102122.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221201131 is a prime.

It is a super-2 number, since 2×221201131² = 97859880711358322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221201137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110600565 + 110600566.

It is an arithmetic number, because the mean of its divisors is an integer number (110600566).

Almost surely, 2^221201131 is an apocalyptic number.

221201131 is a deficient number, since it is larger than the sum of its proper divisors (1).

221201131 is an equidigital number, since it uses as much as digits as its factorization.

221201131 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 221201131 is about 14872.8319764596. The cubic root of 221201131 is about 604.7777167608. Note that the first 4 decimals are identical.

Adding to 221201131 its reverse (131102122), we get a palindrome (352303253).

Subtracting from 221201131 its reverse (131102122), we obtain a palindrome (90099009).

The spelling of 221201131 in words is "two hundred twenty-one million, two hundred one thousand, one hundred thirty-one".