21132312101 has 4 divisors (see below), whose sum is σ = 21369753900. Its totient is φ = 20894870304.

The previous prime is 21132312073. The next prime is 21132312119. The reversal of 21132312101 is 10121323112.

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 2431476100 + 18700836001 = 49310^2 + 136751^2 .

It is a cyclic number.

It is not a de Polignac number, because 21132312101 - 2¹⁰ = 21132311077 is a prime.

It is a super-2 number, since 2×21132312101² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21132312101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21132312121) 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, 118720766 + ... + 118720943.

It is an arithmetic number, because the mean of its divisors is an integer number (5342438475).

Almost surely, 2^21132312101 is an apocalyptic number.

It is an amenable number.

21132312101 is a deficient number, since it is larger than the sum of its proper divisors (237441799).

21132312101 is an equidigital number, since it uses as much as digits as its factorization.

21132312101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237441798.

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

Adding to 21132312101 its reverse (10121323112), we get a palindrome (31253635213).

The spelling of 21132312101 in words is "twenty-one billion, one hundred thirty-two million, three hundred twelve thousand, one hundred one".