221841937 has 2 divisors, whose sum is σ = 221841938. Its totient is φ = 221841936.

The previous prime is 221841911. The next prime is 221841953. The reversal of 221841937 is 739148122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 158734801 + 63107136 = 12599^2 + 7944^2 .

It is a cyclic number.

It is not a de Polignac number, because 221841937 - 2²³ = 213453329 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221841896 and 221841905.

It is not a weakly prime, because it can be changed into another prime (221841337) 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, 110920968 + 110920969.

It is an arithmetic number, because the mean of its divisors is an integer number (110920969).

Almost surely, 2^221841937 is an apocalyptic number.

It is an amenable number.

221841937 is a deficient number, since it is larger than the sum of its proper divisors (1).

221841937 is an equidigital number, since it uses as much as digits as its factorization.

221841937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 37.

The square root of 221841937 is about 14894.3592342873. The cubic root of 221841937 is about 605.3611549459.

It can be divided in two parts, 221841 and 937, that added together give a triangular number (222778 = T₆₆₇).

The spelling of 221841937 in words is "two hundred twenty-one million, eight hundred forty-one thousand, nine hundred thirty-seven".