21553514453 has 4 divisors (see below), whose sum is σ = 21567594048. Its totient is φ = 21539434860.

The previous prime is 21553514449. The next prime is 21553514459. The reversal of 21553514453 is 35441535512.

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 21553514453 - 2² = 21553514449 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21553514459) 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, 7037501 + ... + 7040562.

It is an arithmetic number, because the mean of its divisors is an integer number (5391898512).

Almost surely, 2^21553514453 is an apocalyptic number.

It is an amenable number.

21553514453 is a deficient number, since it is larger than the sum of its proper divisors (14079595).

21553514453 is a wasteful number, since it uses less digits than its factorization.

21553514453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14079594.

The product of its digits is 180000, while the sum is 38.

The spelling of 21553514453 in words is "twenty-one billion, five hundred fifty-three million, five hundred fourteen thousand, four hundred fifty-three".