21133021001 has 4 divisors (see below), whose sum is σ = 21294341904. Its totient is φ = 20971700100.

The previous prime is 21133020947. The next prime is 21133021003. The reversal of 21133021001 is 10012033112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21133021001 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21133021003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 80660255 + ... + 80660516.

It is an arithmetic number, because the mean of its divisors is an integer number (5323585476).

Almost surely, 2^21133021001 is an apocalyptic number.

It is an amenable number.

21133021001 is a deficient number, since it is larger than the sum of its proper divisors (161320903).

21133021001 is a wasteful number, since it uses less digits than its factorization.

21133021001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161320902.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 21133021001 its reverse (10012033112), we get a palindrome (31145054113).

The spelling of 21133021001 in words is "twenty-one billion, one hundred thirty-three million, twenty-one thousand, one".