21709860983 has 2 divisors, whose sum is σ = 21709860984. Its totient is φ = 21709860982.

The previous prime is 21709860973. The next prime is 21709860989. The reversal of 21709860983 is 38906890712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21709860983 - 2¹⁸ = 21709598839 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21709860989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10854930491 + 10854930492.

It is an arithmetic number, because the mean of its divisors is an integer number (10854930492).

Almost surely, 2^21709860983 is an apocalyptic number.

21709860983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21709860983 is an equidigital number, since it uses as much as digits as its factorization.

21709860983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1306368, while the sum is 53.

The spelling of 21709860983 in words is "twenty-one billion, seven hundred nine million, eight hundred sixty thousand, nine hundred eighty-three".