21312321147653 has 2 divisors, whose sum is σ = 21312321147654. Its totient is φ = 21312321147652.

The previous prime is 21312321147647. The next prime is 21312321147673. The reversal of 21312321147653 is 35674112321312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20271182536609 + 1041138611044 = 4502353^2 + 1020362^2 .

It is a cyclic number.

It is not a de Polignac number, because 21312321147653 - 2³⁴ = 21295141278469 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21312321147653.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21312321147673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656160573826 + 10656160573827.

It is an arithmetic number, because the mean of its divisors is an integer number (10656160573827).

Almost surely, 2^{21312321147653} is an apocalyptic number.

It is an amenable number.

21312321147653 is a deficient number, since it is larger than the sum of its proper divisors (1).

21312321147653 is an equidigital number, since it uses as much as digits as its factorization.

21312321147653 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 41.

Adding to 21312321147653 its reverse (35674112321312), we get a palindrome (56986433468965).

The spelling of 21312321147653 in words is "twenty-one trillion, three hundred twelve billion, three hundred twenty-one million, one hundred forty-seven thousand, six hundred fifty-three".