21805248124801 has 4 divisors (see below), whose sum is σ = 21813411829504. Its totient is φ = 21797084420100.

The previous prime is 21805248124729. The next prime is 21805248124813. The reversal of 21805248124801 is 10842184250812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21805248124801 - 2²³ = 21805239736193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21805248127801) 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, 4081848345 + ... + 4081853686.

It is an arithmetic number, because the mean of its divisors is an integer number (5453352957376).

Almost surely, 2^{21805248124801} is an apocalyptic number.

It is an amenable number.

21805248124801 is a deficient number, since it is larger than the sum of its proper divisors (8163704703).

21805248124801 is an equidigital number, since it uses as much as digits as its factorization.

21805248124801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8163704702.

The product of its (nonzero) digits is 327680, while the sum is 46.

The spelling of 21805248124801 in words is "twenty-one trillion, eight hundred five billion, two hundred forty-eight million, one hundred twenty-four thousand, eight hundred one".