21033331001 has 4 divisors (see below), whose sum is σ = 21040685604. Its totient is φ = 21025976400.

The previous prime is 21033330979. The next prime is 21033331013. The reversal of 21033331001 is 10013333012.

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 14921844025 + 6111486976 = 122155^2 + 78176^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033331001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21033331301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3673010 + ... + 3678731.

It is an arithmetic number, because the mean of its divisors is an integer number (5260171401).

Almost surely, 2^21033331001 is an apocalyptic number.

It is an amenable number.

21033331001 is a deficient number, since it is larger than the sum of its proper divisors (7354603).

21033331001 is an equidigital number, since it uses as much as digits as its factorization.

21033331001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7354602.

The product of its (nonzero) digits is 162, while the sum is 17.

Adding to 21033331001 its reverse (10013333012), we get a palindrome (31046664013).

The spelling of 21033331001 in words is "twenty-one billion, thirty-three million, three hundred thirty-one thousand, one".