21665448059 has 2 divisors, whose sum is σ = 21665448060. Its totient is φ = 21665448058.

The previous prime is 21665448043. The next prime is 21665448097. The reversal of 21665448059 is 95084456612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21665448059 - 2⁴ = 21665448043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21665447998 and 21665448016.

It is not a weakly prime, because it can be changed into another prime (21665448029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10832724029 + 10832724030.

It is an arithmetic number, because the mean of its divisors is an integer number (10832724030).

Almost surely, 2^21665448059 is an apocalyptic number.

21665448059 is a deficient number, since it is larger than the sum of its proper divisors (1).

21665448059 is an equidigital number, since it uses as much as digits as its factorization.

21665448059 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2073600, while the sum is 50.

The spelling of 21665448059 in words is "twenty-one billion, six hundred sixty-five million, four hundred forty-eight thousand, fifty-nine".