450221661 has 18 divisors (see below), whose sum is σ = 668389722. Its totient is φ = 292027680.

The previous prime is 450221647. The next prime is 450221669. The reversal of 450221661 is 166122054.

It can be written as a sum of positive squares in 3 ways, for example, as 368409636 + 81812025 = 19194^2 + 9045^2 .

It is not a de Polignac number, because 450221661 - 2¹¹ = 450219613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (450221669) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5950 + ... + 30591.

Almost surely, 2^450221661 is an apocalyptic number.

It is an amenable number.

450221661 is a deficient number, since it is larger than the sum of its proper divisors (218168061).

450221661 is a wasteful number, since it uses less digits than its factorization.

450221661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36621 (or 36581 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 450221661 is about 21218.4273922456. The cubic root of 450221661 is about 766.4352346400.

It can be divided in two parts, 450 and 221661, that added together give a triangular number (222111 = T₆₆₆).

The spelling of 450221661 in words is "four hundred fifty million, two hundred twenty-one thousand, six hundred sixty-one".