21020211029 has 2 divisors, whose sum is σ = 21020211030. Its totient is φ = 21020211028.

The previous prime is 21020211011. The next prime is 21020211041. The reversal of 21020211029 is 92011202012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18264171025 + 2756040004 = 135145^2 + 52498^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21020211029 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21020211029.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21020211529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510105514 + 10510105515.

It is an arithmetic number, because the mean of its divisors is an integer number (10510105515).

Almost surely, 2^21020211029 is an apocalyptic number.

It is an amenable number.

21020211029 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020211029 is an equidigital number, since it uses as much as digits as its factorization.

21020211029 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 20.

The spelling of 21020211029 in words is "twenty-one billion, twenty million, two hundred eleven thousand, twenty-nine".