184981981 has 16 divisors (see below), whose sum is σ = 208113840. Its totient is φ = 163537920.

The previous prime is 184981963. The next prime is 184981997. The reversal of 184981981 is 189189481.

It can be written as a sum of positive squares in 8 ways, for example, as 8357881 + 176624100 = 2891^2 + 13290^2 .

It is a cyclic number.

It is not a de Polignac number, because 184981981 - 2⁵ = 184981949 is a prime.

It is a super-2 number, since 2×184981981² = 68436666589368722, which 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 (184981931) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13171 + ... + 23311.

It is an arithmetic number, because the mean of its divisors is an integer number (13007115).

Almost surely, 2^184981981 is an apocalyptic number.

It is an amenable number.

184981981 is a deficient number, since it is larger than the sum of its proper divisors (23131859).

184981981 is a wasteful number, since it uses less digits than its factorization.

184981981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10224.

The product of its digits is 165888, while the sum is 49.

The square root of 184981981 is about 13600.8081009916. The cubic root of 184981981 is about 569.7834213608.

The spelling of 184981981 in words is "one hundred eighty-four million, nine hundred eighty-one thousand, nine hundred eighty-one".