21673989479 has 2 divisors, whose sum is σ = 21673989480. Its totient is φ = 21673989478.

The previous prime is 21673989461. The next prime is 21673989539. The reversal of 21673989479 is 97498937612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21673989479 - 2¹² = 21673985383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21673989409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10836994739 + 10836994740.

It is an arithmetic number, because the mean of its divisors is an integer number (10836994740).

Almost surely, 2^21673989479 is an apocalyptic number.

21673989479 is a deficient number, since it is larger than the sum of its proper divisors (1).

21673989479 is an equidigital number, since it uses as much as digits as its factorization.

21673989479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41150592, while the sum is 65.

The spelling of 21673989479 in words is "twenty-one billion, six hundred seventy-three million, nine hundred eighty-nine thousand, four hundred seventy-nine".