21928123551 has 8 divisors (see below), whose sum is σ = 29245395760. Its totient is φ = 14614800192.

The previous prime is 21928123541. The next prime is 21928123559. The reversal of 21928123551 is 15532182912.

It is a happy number.

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

It is not a de Polignac number, because 21928123551 - 2¹¹ = 21928121503 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 (21928123559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 974230 + ... + 996483.

It is an arithmetic number, because the mean of its divisors is an integer number (3655674470).

Almost surely, 2^21928123551 is an apocalyptic number.

21928123551 is a deficient number, since it is larger than the sum of its proper divisors (7317272209).

21928123551 is a wasteful number, since it uses less digits than its factorization.

21928123551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1974425.

The product of its digits is 43200, while the sum is 39.

The spelling of 21928123551 in words is "twenty-one billion, nine hundred twenty-eight million, one hundred twenty-three thousand, five hundred fifty-one".