221250551 has 2 divisors, whose sum is σ = 221250552. Its totient is φ = 221250550.

The previous prime is 221250539. The next prime is 221250553. The reversal of 221250551 is 155052122.

221250551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221250551 - 2⁶ = 221250487 is a prime.

Together with 221250553, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221250553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110625275 + 110625276.

It is an arithmetic number, because the mean of its divisors is an integer number (110625276).

Almost surely, 2^221250551 is an apocalyptic number.

221250551 is a deficient number, since it is larger than the sum of its proper divisors (1).

221250551 is an equidigital number, since it uses as much as digits as its factorization.

221250551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 221250551 is about 14874.4933022944. The cubic root of 221250551 is about 604.8227525299.

The spelling of 221250551 in words is "two hundred twenty-one million, two hundred fifty thousand, five hundred fifty-one".