21453758767451 has 4 divisors (see below), whose sum is σ = 21454124924904. Its totient is φ = 21453392610000.

The previous prime is 21453758767447. The next prime is 21453758767471. The reversal of 21453758767451 is 15476785735412.

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 21453758767451 - 2² = 21453758767447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21453758767471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 182990825 + ... + 183108026.

It is an arithmetic number, because the mean of its divisors is an integer number (5363531231226).

Almost surely, 2^{21453758767451} is an apocalyptic number.

21453758767451 is a deficient number, since it is larger than the sum of its proper divisors (366157453).

21453758767451 is an equidigital number, since it uses as much as digits as its factorization.

21453758767451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 366157452.

The product of its digits is 197568000, while the sum is 65.

The spelling of 21453758767451 in words is "twenty-one trillion, four hundred fifty-three billion, seven hundred fifty-eight million, seven hundred sixty-seven thousand, four hundred fifty-one".