21673561683 has 4 divisors (see below), whose sum is σ = 28898082248. Its totient is φ = 14449041120.

The previous prime is 21673561661. The next prime is 21673561727. The reversal of 21673561683 is 38616537612.

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

It is not a de Polignac number, because 21673561683 - 2¹⁰ = 21673560659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21673561633) 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 3 ways as a sum of consecutive naturals, for example, 3612260278 + ... + 3612260283.

It is an arithmetic number, because the mean of its divisors is an integer number (7224520562).

Almost surely, 2^21673561683 is an apocalyptic number.

21673561683 is a deficient number, since it is larger than the sum of its proper divisors (7224520565).

21673561683 is an equidigital number, since it uses as much as digits as its factorization.

21673561683 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7224520564.

The product of its digits is 1088640, while the sum is 48.

The spelling of 21673561683 in words is "twenty-one billion, six hundred seventy-three million, five hundred sixty-one thousand, six hundred eighty-three".