966661562981 has 4 divisors (see below), whose sum is σ = 966664834764. Its totient is φ = 966658291200.

The previous prime is 966661562963. The next prime is 966661562989. The reversal of 966661562981 is 189265166669.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 806061000481 + 160600562500 = 897809^2 + 400750^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-966661562981 is a prime.

It is a super-2 number, since 2×966661562981² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (966661562989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1143260 + ... + 1800101.

It is an arithmetic number, because the mean of its divisors is an integer number (241666208691).

Almost surely, 2^966661562981 is an apocalyptic number.

It is an amenable number.

966661562981 is a deficient number, since it is larger than the sum of its proper divisors (3271783).

966661562981 is a wasteful number, since it uses less digits than its factorization.

966661562981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3271782.

The product of its digits is 50388480, while the sum is 65.

The spelling of 966661562981 in words is "nine hundred sixty-six billion, six hundred sixty-one million, five hundred sixty-two thousand, nine hundred eighty-one".