21032101021 has 4 divisors (see below), whose sum is σ = 22269283452. Its totient is φ = 19794918592.

The previous prime is 21032101007. The next prime is 21032101037. The reversal of 21032101021 is 12010123012.

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 9278505625 + 11753595396 = 96325^2 + 108414^2 .

It is not a de Polignac number, because 21032101021 - 2⁵ = 21032100989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21032100992 and 21032101010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21032105021) 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, 618591190 + ... + 618591223.

It is an arithmetic number, because the mean of its divisors is an integer number (5567320863).

Almost surely, 2^21032101021 is an apocalyptic number.

It is an amenable number.

21032101021 is a deficient number, since it is larger than the sum of its proper divisors (1237182431).

21032101021 is a wasteful number, since it uses less digits than its factorization.

21032101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237182430.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21032101021 its reverse (12010123012), we get a palindrome (33042224033).

The spelling of 21032101021 in words is "twenty-one billion, thirty-two million, one hundred one thousand, twenty-one".