21126763553 has 8 divisors (see below), whose sum is σ = 24150921408. Its totient is φ = 18104117904.

The previous prime is 21126763547. The next prime is 21126763589. The reversal of 21126763553 is 35536762112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21126763553 - 2³² = 16831796257 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21126763553.

It is not an unprimeable number, because it can be changed into a prime (21126783553) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 347951 + ... + 404132.

It is an arithmetic number, because the mean of its divisors is an integer number (3018865176).

Almost surely, 2^21126763553 is an apocalyptic number.

It is an amenable number.

21126763553 is a deficient number, since it is larger than the sum of its proper divisors (3024157855).

21126763553 is an equidigital number, since it uses as much as digits as its factorization.

21126763553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 756103.

The product of its digits is 226800, while the sum is 41.

The spelling of 21126763553 in words is "twenty-one billion, one hundred twenty-six million, seven hundred sixty-three thousand, five hundred fifty-three".