21010020133 has 4 divisors (see below), whose sum is σ = 21011914080. Its totient is φ = 21008126188.

The previous prime is 21010020131. The next prime is 21010020173. The reversal of 21010020133 is 33102001012.

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 not a de Polignac number, because 21010020133 - 2¹ = 21010020131 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 (21010020131) 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, 930235 + ... + 952552.

It is an arithmetic number, because the mean of its divisors is an integer number (5252978520).

Almost surely, 2^21010020133 is an apocalyptic number.

It is an amenable number.

21010020133 is a deficient number, since it is larger than the sum of its proper divisors (1893947).

21010020133 is a wasteful number, since it uses less digits than its factorization.

21010020133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1893946.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21010020133 its reverse (33102001012), we get a palindrome (54112021145).

The spelling of 21010020133 in words is "twenty-one billion, ten million, twenty thousand, one hundred thirty-three".