21002332541 has 4 divisors (see below), whose sum is σ = 21005781084. Its totient is φ = 20998884000.

The previous prime is 21002332517. The next prime is 21002332609. The reversal of 21002332541 is 14523320012.

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 17326456900 + 3675875641 = 131630^2 + 60629^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002332541 - 2¹⁴ = 21002316157 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 (21002532541) 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, 1715120 + ... + 1727321.

It is an arithmetic number, because the mean of its divisors is an integer number (5251445271).

Almost surely, 2^21002332541 is an apocalyptic number.

It is an amenable number.

21002332541 is a deficient number, since it is larger than the sum of its proper divisors (3448543).

21002332541 is an equidigital number, since it uses as much as digits as its factorization.

21002332541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3448542.

The product of its (nonzero) digits is 1440, while the sum is 23.

Adding to 21002332541 its reverse (14523320012), we get a palindrome (35525652553).

The spelling of 21002332541 in words is "twenty-one billion, two million, three hundred thirty-two thousand, five hundred forty-one".