221599541 has 2 divisors, whose sum is σ = 221599542. Its totient is φ = 221599540.

The previous prime is 221599531. The next prime is 221599559. The reversal of 221599541 is 145995122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 137968516 + 83631025 = 11746^2 + 9145^2 .

It is a cyclic number.

It is not a de Polignac number, because 221599541 - 2¹⁸ = 221337397 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221599495 and 221599504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221599531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110799770 + 110799771.

It is an arithmetic number, because the mean of its divisors is an integer number (110799771).

Almost surely, 2^221599541 is an apocalyptic number.

It is an amenable number.

221599541 is a deficient number, since it is larger than the sum of its proper divisors (1).

221599541 is an equidigital number, since it uses as much as digits as its factorization.

221599541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32400, while the sum is 38.

The square root of 221599541 is about 14886.2198358079. The cubic root of 221599541 is about 605.1405916007.

The spelling of 221599541 in words is "two hundred twenty-one million, five hundred ninety-nine thousand, five hundred forty-one".