221440121251 has 2 divisors, whose sum is σ = 221440121252. Its totient is φ = 221440121250.

The previous prime is 221440121239. The next prime is 221440121311. The reversal of 221440121251 is 152121044122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221440121251 - 2⁹ = 221440120739 is a prime.

It is not a weakly prime, because it can be changed into another prime (221440121951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110720060625 + 110720060626.

It is an arithmetic number, because the mean of its divisors is an integer number (110720060626).

Almost surely, 2^221440121251 is an apocalyptic number.

221440121251 is a deficient number, since it is larger than the sum of its proper divisors (1).

221440121251 is an equidigital number, since it uses as much as digits as its factorization.

221440121251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1280, while the sum is 25.

Adding to 221440121251 its reverse (152121044122), we get a palindrome (373561165373).

The spelling of 221440121251 in words is "two hundred twenty-one billion, four hundred forty million, one hundred twenty-one thousand, two hundred fifty-one".