21761453563 has 4 divisors (see below), whose sum is σ = 22463435968. Its totient is φ = 21059471160.

The previous prime is 21761453557. The next prime is 21761453569. The reversal of 21761453563 is 36535416712.

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

It is an interprime number because it is at equal distance from previous prime (21761453557) and next prime (21761453569).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21761453563 is a prime.

It is a super-2 number, since 2×21761453563² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21761453569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 350991156 + ... + 350991217.

It is an arithmetic number, because the mean of its divisors is an integer number (5615858992).

Almost surely, 2^21761453563 is an apocalyptic number.

21761453563 is a deficient number, since it is larger than the sum of its proper divisors (701982405).

21761453563 is an equidigital number, since it uses as much as digits as its factorization.

21761453563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 701982404.

The product of its digits is 453600, while the sum is 43.

The spelling of 21761453563 in words is "twenty-one billion, seven hundred sixty-one million, four hundred fifty-three thousand, five hundred sixty-three".