21580808101 has 4 divisors (see below), whose sum is σ = 21581849952. Its totient is φ = 21579766252.

The previous prime is 21580808087. The next prime is 21580808111. The reversal of 21580808101 is 10180808512.

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 21580808101 - 2⁷ = 21580807973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21580808111) 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, 489211 + ... + 531496.

It is an arithmetic number, because the mean of its divisors is an integer number (5395462488).

Almost surely, 2^21580808101 is an apocalyptic number.

It is an amenable number.

21580808101 is a deficient number, since it is larger than the sum of its proper divisors (1041851).

21580808101 is a wasteful number, since it uses less digits than its factorization.

21580808101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041850.

The product of its (nonzero) digits is 5120, while the sum is 34.

The spelling of 21580808101 in words is "twenty-one billion, five hundred eighty million, eight hundred eight thousand, one hundred one".