21101820200291 has 4 divisors (see below), whose sum is σ = 21102203166000. Its totient is φ = 21101437234584.

The previous prime is 21101820200269. The next prime is 21101820200341. The reversal of 21101820200291 is 19200202810112.

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 21101820200291 - 2¹⁰ = 21101820199267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21101820200221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 191400191 + ... + 191510408.

It is an arithmetic number, because the mean of its divisors is an integer number (5275550791500).

Almost surely, 2^{21101820200291} is an apocalyptic number.

21101820200291 is a deficient number, since it is larger than the sum of its proper divisors (382965709).

21101820200291 is an equidigital number, since it uses as much as digits as its factorization.

21101820200291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382965708.

The product of its (nonzero) digits is 1152, while the sum is 29.

The spelling of 21101820200291 in words is "twenty-one trillion, one hundred one billion, eight hundred twenty million, two hundred thousand, two hundred ninety-one".