21020032331689 has 2 divisors, whose sum is σ = 21020032331690. Its totient is φ = 21020032331688.

The previous prime is 21020032331579. The next prime is 21020032331699. The reversal of 21020032331689 is 98613323002012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17221462515625 + 3798569816064 = 4149875^2 + 1948992^2 .

It is a cyclic number.

It is not a de Polignac number, because 21020032331689 - 2¹³ = 21020032323497 is a prime.

It is a super-2 number, since 2×21020032331689² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21020032331699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510016165844 + 10510016165845.

It is an arithmetic number, because the mean of its divisors is an integer number (10510016165845).

Almost surely, 2^{21020032331689} is an apocalyptic number.

It is an amenable number.

21020032331689 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020032331689 is an equidigital number, since it uses as much as digits as its factorization.

21020032331689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 40.

It can be divided in two parts, 210200323 and 31689, that added together give a palindrome (210232012).

The spelling of 21020032331689 in words is "twenty-one trillion, twenty billion, thirty-two million, three hundred thirty-one thousand, six hundred eighty-nine".