21064742429 has 2 divisors, whose sum is σ = 21064742430. Its totient is φ = 21064742428.

The previous prime is 21064742359. The next prime is 21064742443. The reversal of 21064742429 is 92424746012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19799304100 + 1265438329 = 140710^2 + 35573^2 .

It is a cyclic number.

It is not a de Polignac number, because 21064742429 - 2⁸ = 21064742173 is a prime.

It is a super-2 number, since 2×21064742429² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21064742729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10532371214 + 10532371215.

It is an arithmetic number, because the mean of its divisors is an integer number (10532371215).

Almost surely, 2^21064742429 is an apocalyptic number.

It is an amenable number.

21064742429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21064742429 is an equidigital number, since it uses as much as digits as its factorization.

21064742429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 193536, while the sum is 41.

The spelling of 21064742429 in words is "twenty-one billion, sixty-four million, seven hundred forty-two thousand, four hundred twenty-nine".