21706182487049 has 2 divisors, whose sum is σ = 21706182487050. Its totient is φ = 21706182487048.

The previous prime is 21706182487013. The next prime is 21706182487057. The reversal of 21706182487049 is 94078428160712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10965932905225 + 10740249581824 = 3311485^2 + 3277232^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21706182487049 is a prime.

It is a super-2 number, since 2×21706182487049² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21706182486049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10853091243524 + 10853091243525.

It is an arithmetic number, because the mean of its divisors is an integer number (10853091243525).

Almost surely, 2^{21706182487049} is an apocalyptic number.

It is an amenable number.

21706182487049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21706182487049 is an equidigital number, since it uses as much as digits as its factorization.

21706182487049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10838016, while the sum is 59.

The spelling of 21706182487049 in words is "twenty-one trillion, seven hundred six billion, one hundred eighty-two million, four hundred eighty-seven thousand, forty-nine".