21001212010133 has 4 divisors (see below), whose sum is σ = 21038514341088. Its totient is φ = 20963909679180.

The previous prime is 21001212010057. The next prime is 21001212010189. The reversal of 21001212010133 is 33101021210012.

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 21001212010133 - 2²⁰ = 21001210961557 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 (21001212010033) 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, 18651164633 + ... + 18651165758.

It is an arithmetic number, because the mean of its divisors is an integer number (5259628585272).

Almost surely, 2^{21001212010133} is an apocalyptic number.

It is an amenable number.

21001212010133 is a deficient number, since it is larger than the sum of its proper divisors (37302330955).

21001212010133 is an equidigital number, since it uses as much as digits as its factorization.

21001212010133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37302330954.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21001212010133 its reverse (33101021210012), we get a palindrome (54102233220145).

The spelling of 21001212010133 in words is "twenty-one trillion, one billion, two hundred twelve million, ten thousand, one hundred thirty-three".