21546340163 has 4 divisors (see below), whose sum is σ = 22289317440. Its totient is φ = 20803362888.

The previous prime is 21546340139. The next prime is 21546340181. The reversal of 21546340163 is 36104364512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21546340163 - 2¹² = 21546336067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21546340103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 371488595 + ... + 371488652.

It is an arithmetic number, because the mean of its divisors is an integer number (5572329360).

Almost surely, 2^21546340163 is an apocalyptic number.

21546340163 is a deficient number, since it is larger than the sum of its proper divisors (742977277).

21546340163 is an equidigital number, since it uses as much as digits as its factorization.

21546340163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742977276.

The product of its (nonzero) digits is 51840, while the sum is 35.

The spelling of 21546340163 in words is "twenty-one billion, five hundred forty-six million, three hundred forty thousand, one hundred sixty-three".