21016010961 has 81 divisors (see below), whose sum is σ = 35064412201. Its totient is φ = 12119408400.

The previous prime is 21016010921. The next prime is 21016011001. The reversal of 21016010961 is 16901061012.

The square root of 21016010961 is 144969.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (21016010921) and next prime (21016011001).

It is not a de Polignac number, because 21016010961 - 2¹¹ = 21016008913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21016010921) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 110031376 + ... + 110031566.

Almost surely, 2^21016010961 is an apocalyptic number.

21016010961 is the 144969-th square number.

21016010961 is the 72485-th centered octagonal number.

It is an amenable number.

21016010961 is a deficient number, since it is larger than the sum of its proper divisors (14048401240).

21016010961 is a wasteful number, since it uses less digits than its factorization.

21016010961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

Adding to 21016010961 its reverse (16901061012), we get a palindrome (37917071973).

The spelling of 21016010961 in words is "twenty-one billion, sixteen million, ten thousand, nine hundred sixty-one".