221349637 has 2 divisors, whose sum is σ = 221349638. Its totient is φ = 221349636.

The previous prime is 221349619. The next prime is 221349647. The reversal of 221349637 is 736943122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 212022721 + 9326916 = 14561^2 + 3054^2 .

It is a cyclic number.

It is not a de Polignac number, because 221349637 - 2¹⁹ = 220825349 is a prime.

It is equal to p_12192778 and since 221349637 and 12192778 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 221349596 and 221349605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221349647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110674818 + 110674819.

It is an arithmetic number, because the mean of its divisors is an integer number (110674819).

Almost surely, 2^221349637 is an apocalyptic number.

It is an amenable number.

221349637 is a deficient number, since it is larger than the sum of its proper divisors (1).

221349637 is an equidigital number, since it uses as much as digits as its factorization.

221349637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 37.

The square root of 221349637 is about 14877.8236647703. The cubic root of 221349637 is about 604.9130280462.

The spelling of 221349637 in words is "two hundred twenty-one million, three hundred forty-nine thousand, six hundred thirty-seven".