187914447081 has 9 divisors (see below), whose sum is σ = 271433857591. Its totient is φ = 125275431072.

The previous prime is 187914447079. The next prime is 187914447113. The reversal of 187914447081 is 180744419781.

The square root of 187914447081 is 433491.

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

187914447081 is a `hidden beast` number, since 1 + 8 + 7 + 91 + 4 + 4 + 470 + 81 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1622075625 + 186292371456 = 40275^2 + 431616^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 187914447081 - 2¹ = 187914447079 is a prime.

It is a super-2 number, since 2×187914447081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (187914447481) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1228225 + ... + 1372721.

Almost surely, 2^187914447081 is an apocalyptic number.

187914447081 is the 433491-st square number.

187914447081 is the 216746-th centered octagonal number.

It is an amenable number.

187914447081 is a deficient number, since it is larger than the sum of its proper divisors (83519410510).

187914447081 is an frugal number, since it uses more digits than its factorization.

187914447081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289000 (or 144500 counting only the distinct ones).

The product of its (nonzero) digits is 1806336, while the sum is 54.

The spelling of 187914447081 in words is "one hundred eighty-seven billion, nine hundred fourteen million, four hundred forty-seven thousand, eighty-one".