21020311129 has 16 divisors (see below), whose sum is σ = 21936361536. Its totient is φ = 20123294400.

The previous prime is 21020311127. The next prime is 21020311153. The reversal of 21020311129 is 92111302012.

It is a cyclic number.

It is not a de Polignac number, because 21020311129 - 2¹ = 21020311127 is a prime.

It is a super-2 number, since 2×21020311129² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21020311121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2328234 + ... + 2337244.

It is an arithmetic number, because the mean of its divisors is an integer number (1371022596).

Almost surely, 2^21020311129 is an apocalyptic number.

It is an amenable number.

21020311129 is a deficient number, since it is larger than the sum of its proper divisors (916050407).

21020311129 is an equidigital number, since it uses as much as digits as its factorization.

21020311129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10056.

The product of its (nonzero) digits is 216, while the sum is 22.

The spelling of 21020311129 in words is "twenty-one billion, twenty million, three hundred eleven thousand, one hundred twenty-nine".