21641402113 has 4 divisors (see below), whose sum is σ = 21641869060. Its totient is φ = 21640935168.

The previous prime is 21641402089. The next prime is 21641402117. The reversal of 21641402113 is 31120414612.

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 245611584 + 21395790529 = 15672^2 + 146273^2 .

It is a cyclic number.

It is not a de Polignac number, because 21641402113 - 2³³ = 13051467521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21641402117) 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, 155208 + ... + 259561.

It is an arithmetic number, because the mean of its divisors is an integer number (5410467265).

Almost surely, 2^21641402113 is an apocalyptic number.

It is an amenable number.

21641402113 is a deficient number, since it is larger than the sum of its proper divisors (466947).

21641402113 is an equidigital number, since it uses as much as digits as its factorization.

21641402113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466946.

The product of its (nonzero) digits is 1152, while the sum is 25.

Adding to 21641402113 its reverse (31120414612), we get a palindrome (52761816725).

The spelling of 21641402113 in words is "twenty-one billion, six hundred forty-one million, four hundred two thousand, one hundred thirteen".