21630551223 has 4 divisors (see below), whose sum is σ = 28840734968. Its totient is φ = 14420367480.

The previous prime is 21630551219. The next prime is 21630551249. The reversal of 21630551223 is 32215503612.

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

It is not a de Polignac number, because 21630551223 - 2² = 21630551219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21630551263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3605091868 + ... + 3605091873.

It is an arithmetic number, because the mean of its divisors is an integer number (7210183742).

Almost surely, 2^21630551223 is an apocalyptic number.

21630551223 is a deficient number, since it is larger than the sum of its proper divisors (7210183745).

21630551223 is an equidigital number, since it uses as much as digits as its factorization.

21630551223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7210183744.

The product of its (nonzero) digits is 10800, while the sum is 30.

The spelling of 21630551223 in words is "twenty-one billion, six hundred thirty million, five hundred fifty-one thousand, two hundred twenty-three".