21000033101 has 4 divisors (see below), whose sum is σ = 21253045632. Its totient is φ = 20747020572.

The previous prime is 21000033079. The next prime is 21000033107. The reversal of 21000033101 is 10133000012.

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-21000033101 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 (21000033107) 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, 126506141 + ... + 126506306.

It is an arithmetic number, because the mean of its divisors is an integer number (5313261408).

Almost surely, 2^21000033101 is an apocalyptic number.

It is an amenable number.

21000033101 is a deficient number, since it is larger than the sum of its proper divisors (253012531).

21000033101 is an equidigital number, since it uses as much as digits as its factorization.

21000033101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253012530.

The product of its (nonzero) digits is 18, while the sum is 11.

Adding to 21000033101 its reverse (10133000012), we get a palindrome (31133033113).

The spelling of 21000033101 in words is "twenty-one billion, thirty-three thousand, one hundred one".