1361663221 has 4 divisors (see below), whose sum is σ = 1373713452. Its totient is φ = 1349612992.

The previous prime is 1361663213. The next prime is 1361663249. The reversal of 1361663221 is 1223661631.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15800625 + 1345862596 = 3975^2 + 36686^2 .

It is a cyclic number.

It is not a de Polignac number, because 1361663221 - 2³ = 1361663213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361663521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6024946 + ... + 6025171.

It is an arithmetic number, because the mean of its divisors is an integer number (343428363).

Almost surely, 2^1361663221 is an apocalyptic number.

It is an amenable number.

1361663221 is a deficient number, since it is larger than the sum of its proper divisors (12050231).

1361663221 is a wasteful number, since it uses less digits than its factorization.

1361663221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12050230.

The product of its digits is 7776, while the sum is 31.

The square root of 1361663221 is about 36900.7211447148. The cubic root of 1361663221 is about 1108.3831181411.

The spelling of 1361663221 in words is "one billion, three hundred sixty-one million, six hundred sixty-three thousand, two hundred twenty-one".