21660196583387 has 2 divisors, whose sum is σ = 21660196583388. Its totient is φ = 21660196583386.

The previous prime is 21660196583341. The next prime is 21660196583429. The reversal of 21660196583387 is 78338569106612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21660196583387 - 2²² = 21660192389083 is a prime.

It is not a weakly prime, because it can be changed into another prime (21660196583087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10830098291693 + 10830098291694.

It is an arithmetic number, because the mean of its divisors is an integer number (10830098291694).

Almost surely, 2^{21660196583387} is an apocalyptic number.

21660196583387 is a deficient number, since it is larger than the sum of its proper divisors (1).

21660196583387 is an equidigital number, since it uses as much as digits as its factorization.

21660196583387 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 78382080, while the sum is 65.

The spelling of 21660196583387 in words is "twenty-one trillion, six hundred sixty billion, one hundred ninety-six million, five hundred eighty-three thousand, three hundred eighty-seven".