21573506207233 has 2 divisors, whose sum is σ = 21573506207234. Its totient is φ = 21573506207232.

The previous prime is 21573506207219. The next prime is 21573506207303. The reversal of 21573506207233 is 33270260537512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21546418643344 + 27087563889 = 4641812^2 + 164583^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21573506207233 is a prime.

It is not a weakly prime, because it can be changed into another prime (21573506202233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10786753103616 + 10786753103617.

It is an arithmetic number, because the mean of its divisors is an integer number (10786753103617).

Almost surely, 2^{21573506207233} is an apocalyptic number.

It is an amenable number.

21573506207233 is a deficient number, since it is larger than the sum of its proper divisors (1).

21573506207233 is an equidigital number, since it uses as much as digits as its factorization.

21573506207233 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1587600, while the sum is 46.

The spelling of 21573506207233 in words is "twenty-one trillion, five hundred seventy-three billion, five hundred six million, two hundred seven thousand, two hundred thirty-three".