221331213137 has 2 divisors, whose sum is σ = 221331213138. Its totient is φ = 221331213136.

The previous prime is 221331213101. The next prime is 221331213157. The reversal of 221331213137 is 731312133122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 146498328001 + 74832885136 = 382751^2 + 273556^2 .

It is a cyclic number.

It is not a de Polignac number, because 221331213137 - 2²⁶ = 221264104273 is a prime.

It is a super-3 number, since 3×221331213137³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (221331213157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110665606568 + 110665606569.

It is an arithmetic number, because the mean of its divisors is an integer number (110665606569).

Almost surely, 2^221331213137 is an apocalyptic number.

It is an amenable number.

221331213137 is a deficient number, since it is larger than the sum of its proper divisors (1).

221331213137 is an equidigital number, since it uses as much as digits as its factorization.

221331213137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 29.

Adding to 221331213137 its reverse (731312133122), we get a palindrome (952643346259).

The spelling of 221331213137 in words is "two hundred twenty-one billion, three hundred thirty-one million, two hundred thirteen thousand, one hundred thirty-seven".