21632105641 has 4 divisors (see below), whose sum is σ = 21680284500. Its totient is φ = 21583926784.

The previous prime is 21632105609. The next prime is 21632105647. The reversal of 21632105641 is 14650123612.

It is a happy number.

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 18277958416 + 3354147225 = 135196^2 + 57915^2 .

It is a cyclic number.

It is not a de Polignac number, because 21632105641 - 2⁵ = 21632105609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21632105647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24088756 + ... + 24089653.

It is an arithmetic number, because the mean of its divisors is an integer number (5420071125).

Almost surely, 2^21632105641 is an apocalyptic number.

It is an amenable number.

21632105641 is a deficient number, since it is larger than the sum of its proper divisors (48178859).

21632105641 is an equidigital number, since it uses as much as digits as its factorization.

21632105641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48178858.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 21632105641 in words is "twenty-one billion, six hundred thirty-two million, one hundred five thousand, six hundred forty-one".