133530021 has 6 divisors (see below), whose sum is σ = 192876710. Its totient is φ = 89020008.

The previous prime is 133530013. The next prime is 133530029. The reversal of 133530021 is 120035331.

133530021 is a `hidden beast` number, since 133 + 530 + 0 + 2 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (133530013) and next prime (133530029).

It can be written as a sum of positive squares in only one way, i.e., 72080100 + 61449921 = 8490^2 + 7839^2 .

It is not a de Polignac number, because 133530021 - 2³ = 133530013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133529976 and 133530003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133530029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7418326 + ... + 7418343.

Almost surely, 2^133530021 is an apocalyptic number.

It is an amenable number.

133530021 is a deficient number, since it is larger than the sum of its proper divisors (59346689).

133530021 is a wasteful number, since it uses less digits than its factorization.

133530021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14836675 (or 14836672 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 18.

The square root of 133530021 is about 11555.5190709894. The cubic root of 133530021 is about 511.1240375310.

Adding to 133530021 its reverse (120035331), we get a palindrome (253565352).

The spelling of 133530021 in words is "one hundred thirty-three million, five hundred thirty thousand, twenty-one".