21000001331331 has 72 divisors (see below), whose sum is σ = 33440218164080. Its totient is φ = 12689650512000.

The previous prime is 21000001331293. The next prime is 21000001331389. The reversal of 21000001331331 is 13313310000012.

It is a happy number.

21000001331331 is a `hidden beast` number, since 2 + 1 + 0 + 0 + 0 + 0 + 0 + 1 + 331 + 331 = 666.

It is not a de Polignac number, because 21000001331331 - 2¹⁰ = 21000001330307 is a prime.

It is a super-2 number, since 2×21000001331331² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000001331531) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1758640821 + ... + 1758652761.

Almost surely, 2^{21000001331331} is an apocalyptic number.

21000001331331 is a deficient number, since it is larger than the sum of its proper divisors (12440216832749).

21000001331331 is a wasteful number, since it uses less digits than its factorization.

21000001331331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16609 (or 16595 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 18.

Adding to 21000001331331 its reverse (13313310000012), we get a palindrome (34313311331343).

The spelling of 21000001331331 in words is "twenty-one trillion, one million, three hundred thirty-one thousand, three hundred thirty-one".