221540633 has 2 divisors, whose sum is σ = 221540634. Its totient is φ = 221540632.

The previous prime is 221540621. The next prime is 221540677. The reversal of 221540633 is 336045122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 191213584 + 30327049 = 13828^2 + 5507^2 .

It is a cyclic number.

It is not a de Polignac number, because 221540633 - 2¹⁶ = 221475097 is a prime.

It is not a weakly prime, because it can be changed into another prime (221540533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110770316 + 110770317.

It is an arithmetic number, because the mean of its divisors is an integer number (110770317).

Almost surely, 2^221540633 is an apocalyptic number.

It is an amenable number.

221540633 is a deficient number, since it is larger than the sum of its proper divisors (1).

221540633 is an equidigital number, since it uses as much as digits as its factorization.

221540633 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 221540633 is about 14884.2410958705. The cubic root of 221540633 is about 605.0869651641.

Adding to 221540633 its reverse (336045122), we get a palindrome (557585755).

The spelling of 221540633 in words is "two hundred twenty-one million, five hundred forty thousand, six hundred thirty-three".