21651342633 has 8 divisors (see below), whose sum is σ = 32076063200. Its totient is φ = 14434228404.

The previous prime is 21651342599. The next prime is 21651342641. The reversal of 21651342633 is 33624315612.

21651342633 is a `hidden beast` number, since 2 + 1 + 6 + 5 + 13 + 4 + 2 + 633 = 666.

It is not a de Polignac number, because 21651342633 - 2¹⁶ = 21651277097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21651342673) 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 7 ways as a sum of consecutive naturals, for example, 400950763 + ... + 400950816.

It is an arithmetic number, because the mean of its divisors is an integer number (4009507900).

Almost surely, 2^21651342633 is an apocalyptic number.

It is an amenable number.

21651342633 is a deficient number, since it is larger than the sum of its proper divisors (10424720567).

21651342633 is an equidigital number, since it uses as much as digits as its factorization.

21651342633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801901588 (or 801901582 counting only the distinct ones).

The product of its digits is 77760, while the sum is 36.

The spelling of 21651342633 in words is "twenty-one billion, six hundred fifty-one million, three hundred forty-two thousand, six hundred thirty-three".