21064552823 has 2 divisors, whose sum is σ = 21064552824. Its totient is φ = 21064552822.

The previous prime is 21064552807. The next prime is 21064552877. The reversal of 21064552823 is 32825546012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21064552823 - 2⁴ = 21064552807 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21064252823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10532276411 + 10532276412.

It is an arithmetic number, because the mean of its divisors is an integer number (10532276412).

Almost surely, 2^21064552823 is an apocalyptic number.

21064552823 is a deficient number, since it is larger than the sum of its proper divisors (1).

21064552823 is an equidigital number, since it uses as much as digits as its factorization.

21064552823 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 115200, while the sum is 38.

The spelling of 21064552823 in words is "twenty-one billion, sixty-four million, five hundred fifty-two thousand, eight hundred twenty-three".