133521161636 has 12 divisors (see below), whose sum is σ = 233666955228. Its totient is φ = 66759174432.

The previous prime is 133521161629. The next prime is 133521161639. The reversal of 133521161636 is 636161125331.

It can be written as a sum of positive squares in 2 ways, for example, as 109160195236 + 24360966400 = 330394^2 + 156080^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 133521161636.

It is not an unprimeable number, because it can be changed into a prime (133521161639) 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, 121211 + ... + 530786.

It is an arithmetic number, because the mean of its divisors is an integer number (19472246269).

Almost surely, 2^133521161636 is an apocalyptic number.

It is an amenable number.

133521161636 is a deficient number, since it is larger than the sum of its proper divisors (100145793592).

133521161636 is a wasteful number, since it uses less digits than its factorization.

133521161636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703198 (or 703196 counting only the distinct ones).

The product of its digits is 58320, while the sum is 38.

Adding to 133521161636 its reverse (636161125331), we get a palindrome (769682286967).

The spelling of 133521161636 in words is "one hundred thirty-three billion, five hundred twenty-one million, one hundred sixty-one thousand, six hundred thirty-six".