1881138173 has 2 divisors, whose sum is σ = 1881138174. Its totient is φ = 1881138172.

The previous prime is 1881138151. The next prime is 1881138209. The reversal of 1881138173 is 3718311881.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1398984409 + 482153764 = 37403^2 + 21958^2 .

It is a cyclic number.

It is not a de Polignac number, because 1881138173 - 2⁶ = 1881138109 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1881138173.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1881138143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 940569086 + 940569087.

It is an arithmetic number, because the mean of its divisors is an integer number (940569087).

Almost surely, 2^1881138173 is an apocalyptic number.

It is an amenable number.

1881138173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1881138173 is an equidigital number, since it uses as much as digits as its factorization.

1881138173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32256, while the sum is 41.

The square root of 1881138173 is about 43372.0897928610. The cubic root of 1881138173 is about 1234.4501746989.

The spelling of 1881138173 in words is "one billion, eight hundred eighty-one million, one hundred thirty-eight thousand, one hundred seventy-three".