21373764453 has 6 divisors (see below), whose sum is σ = 30873215334. Its totient is φ = 14249176296.

The previous prime is 21373764443. The next prime is 21373764479. The reversal of 21373764453 is 35446737312.

21373764453 is a `hidden beast` number, since 2 + 137 + 3 + 7 + 64 + 453 = 666.

It can be written as a sum of positive squares in only one way, i.e., 21280390884 + 93373569 = 145878^2 + 9663^2 .

It is not a de Polignac number, because 21373764453 - 2⁵ = 21373764421 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21373764399 and 21373764408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21373764443) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1187431350 + ... + 1187431367.

It is an arithmetic number, because the mean of its divisors is an integer number (5145535889).

Almost surely, 2^21373764453 is an apocalyptic number.

It is an amenable number.

21373764453 is a deficient number, since it is larger than the sum of its proper divisors (9499450881).

21373764453 is a wasteful number, since it uses less digits than its factorization.

21373764453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2374862723 (or 2374862720 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 45.

The spelling of 21373764453 in words is "twenty-one billion, three hundred seventy-three million, seven hundred sixty-four thousand, four hundred fifty-three".