21653733506239 has 2 divisors, whose sum is σ = 21653733506240. Its totient is φ = 21653733506238.

The previous prime is 21653733506219. The next prime is 21653733506267. The reversal of 21653733506239 is 93260533735612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21653733506239 - 2¹⁷ = 21653733375167 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21653733506239.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21653733506219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10826866753119 + 10826866753120.

It is an arithmetic number, because the mean of its divisors is an integer number (10826866753120).

Almost surely, 2^{21653733506239} is an apocalyptic number.

21653733506239 is a deficient number, since it is larger than the sum of its proper divisors (1).

21653733506239 is an equidigital number, since it uses as much as digits as its factorization.

21653733506239 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18370800, while the sum is 55.

The spelling of 21653733506239 in words is "twenty-one trillion, six hundred fifty-three billion, seven hundred thirty-three million, five hundred six thousand, two hundred thirty-nine".