21453523655143 has 4 divisors (see below), whose sum is σ = 21453539367808. Its totient is φ = 21453507942480.

The previous prime is 21453523655141. The next prime is 21453523655167. The reversal of 21453523655143 is 34155632535412.

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 21453523655143 - 2¹ = 21453523655141 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 (21453523655141) 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, 5590446 + ... + 8611627.

It is an arithmetic number, because the mean of its divisors is an integer number (5363384841952).

Almost surely, 2^{21453523655143} is an apocalyptic number.

21453523655143 is a deficient number, since it is larger than the sum of its proper divisors (15712665).

21453523655143 is a wasteful number, since it uses less digits than its factorization.

21453523655143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15712664.

The product of its digits is 6480000, while the sum is 49.

The spelling of 21453523655143 in words is "twenty-one trillion, four hundred fifty-three billion, five hundred twenty-three million, six hundred fifty-five thousand, one hundred forty-three".