21648747240137 has 2 divisors, whose sum is σ = 21648747240138. Its totient is φ = 21648747240136.

The previous prime is 21648747240103. The next prime is 21648747240143. The reversal of 21648747240137 is 73104274784612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21563541046336 + 85206193801 = 4643656^2 + 291901^2 .

It is a cyclic number.

It is not a de Polignac number, because 21648747240137 - 2²² = 21648743045833 is a prime.

It is a super-3 number, since 3×21648747240137³ (a number of 41 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21648747210137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10824373620068 + 10824373620069.

It is an arithmetic number, because the mean of its divisors is an integer number (10824373620069).

Almost surely, 2^{21648747240137} is an apocalyptic number.

It is an amenable number.

21648747240137 is a deficient number, since it is larger than the sum of its proper divisors (1).

21648747240137 is an equidigital number, since it uses as much as digits as its factorization.

21648747240137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12644352, while the sum is 56.

The spelling of 21648747240137 in words is "twenty-one trillion, six hundred forty-eight billion, seven hundred forty-seven million, two hundred forty thousand, one hundred thirty-seven".