181220487 has 16 divisors (see below), whose sum is σ = 283610112. Its totient is φ = 100755360.

The previous prime is 181220467. The next prime is 181220509. The reversal of 181220487 is 784022181.

It is a happy number.

181220487 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 181220487 - 2¹⁴ = 181204103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181220467) 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, 115839 + ... + 117392.

It is an arithmetic number, because the mean of its divisors is an integer number (17725632).

Almost surely, 2^181220487 is an apocalyptic number.

181220487 is a deficient number, since it is larger than the sum of its proper divisors (102389625).

181220487 is a wasteful number, since it uses less digits than its factorization.

181220487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233278.

The product of its (nonzero) digits is 7168, while the sum is 33.

The square root of 181220487 is about 13461.8158879105. The cubic root of 181220487 is about 565.8948796940.

The spelling of 181220487 in words is "one hundred eighty-one million, two hundred twenty thousand, four hundred eighty-seven".