21468815501 has 4 divisors (see below), whose sum is σ = 24535789152. Its totient is φ = 18401841852.

The previous prime is 21468815477. The next prime is 21468815513. The reversal of 21468815501 is 10551886412.

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 21468815501 - 2²² = 21464621197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21468815531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1533486815 + ... + 1533486828.

It is an arithmetic number, because the mean of its divisors is an integer number (6133947288).

Almost surely, 2^21468815501 is an apocalyptic number.

It is an amenable number.

21468815501 is a deficient number, since it is larger than the sum of its proper divisors (3066973651).

21468815501 is an equidigital number, since it uses as much as digits as its factorization.

21468815501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3066973650.

The product of its (nonzero) digits is 76800, while the sum is 41.

The spelling of 21468815501 in words is "twenty-one billion, four hundred sixty-eight million, eight hundred fifteen thousand, five hundred one".