21454320101 has 4 divisors (see below), whose sum is σ = 21455184492. Its totient is φ = 21453455712.

The previous prime is 21454320067. The next prime is 21454320113. The reversal of 21454320101 is 10102345412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4675003876 + 16779316225 = 68374^2 + 129535^2 .

It is a cyclic number.

It is not a de Polignac number, because 21454320101 - 2¹⁸ = 21454057957 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 (21454320131) 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, 393830 + ... + 444983.

It is an arithmetic number, because the mean of its divisors is an integer number (5363796123).

Almost surely, 2^21454320101 is an apocalyptic number.

It is an amenable number.

21454320101 is a deficient number, since it is larger than the sum of its proper divisors (864391).

21454320101 is an equidigital number, since it uses as much as digits as its factorization.

21454320101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864390.

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21454320101 its reverse (10102345412), we get a palindrome (31556665513).

The spelling of 21454320101 in words is "twenty-one billion, four hundred fifty-four million, three hundred twenty thousand, one hundred one".