1601355221 has 2 divisors, whose sum is σ = 1601355222. Its totient is φ = 1601355220.

The previous prime is 1601355211. The next prime is 1601355233. The reversal of 1601355221 is 1225531061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1585154596 + 16200625 = 39814^2 + 4025^2 .

It is an emirp because it is prime and its reverse (1225531061) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1601355221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1601355211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 800677610 + 800677611.

It is an arithmetic number, because the mean of its divisors is an integer number (800677611).

Almost surely, 2^1601355221 is an apocalyptic number.

It is an amenable number.

1601355221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1601355221 is an equidigital number, since it uses as much as digits as its factorization.

1601355221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 1601355221 is about 40016.9366768622. The cubic root of 1601355221 is about 1169.9372262812.

Adding to 1601355221 its reverse (1225531061), we get a palindrome (2826886282).

The spelling of 1601355221 in words is "one billion, six hundred one million, three hundred fifty-five thousand, two hundred twenty-one".