1633428221 has 8 divisors (see below), whose sum is σ = 1744819704. Its totient is φ = 1523737600.

The previous prime is 1633428211. The next prime is 1633428227. The reversal of 1633428221 is 1228243361.

It can be written as a sum of positive squares in 4 ways, for example, as 302272996 + 1331155225 = 17386^2 + 36485^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1633428221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1633428227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 423230 + ... + 427071.

It is an arithmetic number, because the mean of its divisors is an integer number (218102463).

Almost surely, 2^1633428221 is an apocalyptic number.

It is an amenable number.

1633428221 is a deficient number, since it is larger than the sum of its proper divisors (111391483).

1633428221 is a wasteful number, since it uses less digits than its factorization.

1633428221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 850431.

The product of its digits is 13824, while the sum is 32.

The square root of 1633428221 is about 40415.6927566509. The cubic root of 1633428221 is about 1177.6964110255.

The spelling of 1633428221 in words is "one billion, six hundred thirty-three million, four hundred twenty-eight thousand, two hundred twenty-one".