20684047999 has 2 divisors, whose sum is σ = 20684048000. Its totient is φ = 20684047998.

The previous prime is 20684047939. The next prime is 20684048003. The reversal of 20684047999 is 99974048602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20684047999 - 2¹⁹ = 20683523711 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20684047939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10342023999 + 10342024000.

It is an arithmetic number, because the mean of its divisors is an integer number (10342024000).

Almost surely, 2^20684047999 is an apocalyptic number.

20684047999 is a deficient number, since it is larger than the sum of its proper divisors (1).

20684047999 is an equidigital number, since it uses as much as digits as its factorization.

20684047999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7838208, while the sum is 58.

The spelling of 20684047999 in words is "twenty billion, six hundred eighty-four million, forty-seven thousand, nine hundred ninety-nine".