186564460981 has 4 divisors (see below), whose sum is σ = 188411633964. Its totient is φ = 184717288000.

The previous prime is 186564460967. The next prime is 186564460993. The reversal of 186564460981 is 189064465681.

It is a happy number.

186564460981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 152380148881 + 34184312100 = 390359^2 + 184890^2 .

It is a cyclic number.

It is not a de Polignac number, because 186564460981 - 2⁷ = 186564460853 is a prime.

It is a super-2 number, since 2×186564460981² (a number of 23 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 (186564460961) 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 3 ways as a sum of consecutive naturals, for example, 923586340 + ... + 923586541.

It is an arithmetic number, because the mean of its divisors is an integer number (47102908491).

Almost surely, 2^186564460981 is an apocalyptic number.

It is an amenable number.

186564460981 is a deficient number, since it is larger than the sum of its proper divisors (1847172983).

186564460981 is a wasteful number, since it uses less digits than its factorization.

186564460981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1847172982.

The product of its (nonzero) digits is 9953280, while the sum is 58.

The spelling of 186564460981 in words is "one hundred eighty-six billion, five hundred sixty-four million, four hundred sixty thousand, nine hundred eighty-one".