221252651 has 2 divisors, whose sum is σ = 221252652. Its totient is φ = 221252650.

The previous prime is 221252623. The next prime is 221252659. The reversal of 221252651 is 156252122.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221252651 is a prime.

It is a super-3 number, since 3×221252651³ (a number of 26 digits) contains 333 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221252651.

It is not a weakly prime, because it can be changed into another prime (221252659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110626325 + 110626326.

It is an arithmetic number, because the mean of its divisors is an integer number (110626326).

Almost surely, 2^221252651 is an apocalyptic number.

221252651 is a deficient number, since it is larger than the sum of its proper divisors (1).

221252651 is an equidigital number, since it uses as much as digits as its factorization.

221252651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2400, while the sum is 26.

The square root of 221252651 is about 14874.5638927667. The cubic root of 221252651 is about 604.8246660826.

The spelling of 221252651 in words is "two hundred twenty-one million, two hundred fifty-two thousand, six hundred fifty-one".