21066910937 has 2 divisors, whose sum is σ = 21066910938. Its totient is φ = 21066910936.

The previous prime is 21066910903. The next prime is 21066910951. The reversal of 21066910937 is 73901966012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11685826201 + 9381084736 = 108101^2 + 96856^2 .

It is a cyclic number.

It is not a de Polignac number, because 21066910937 - 2¹² = 21066906841 is a prime.

It is not a weakly prime, because it can be changed into another prime (21066910967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10533455468 + 10533455469.

It is an arithmetic number, because the mean of its divisors is an integer number (10533455469).

Almost surely, 2^21066910937 is an apocalyptic number.

It is an amenable number.

21066910937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21066910937 is an equidigital number, since it uses as much as digits as its factorization.

21066910937 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 122472, while the sum is 44.

The spelling of 21066910937 in words is "twenty-one billion, sixty-six million, nine hundred ten thousand, nine hundred thirty-seven".