189957181 has 16 divisors (see below), whose sum is σ = 199531008. Its totient is φ = 180633600.

The previous prime is 189957143. The next prime is 189957199. The reversal of 189957181 is 181759981.

It is a happy number.

It is a 7-Lehmer number, since φ(189957181) divides (189957181-1)⁷.

It is a cyclic number.

It is not a de Polignac number, because 189957181 - 2²⁵ = 156402749 is a prime.

It is a super-2 number, since 2×189957181² = 72167461226933522, which contains 22 as substring.

It is a Duffinian number.

189957181 is a modest number, since divided by 57181 gives 1899 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189967181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 739005 + ... + 739261.

It is an arithmetic number, because the mean of its divisors is an integer number (12470688).

Almost surely, 2^189957181 is an apocalyptic number.

It is an amenable number.

189957181 is a deficient number, since it is larger than the sum of its proper divisors (9573827).

189957181 is a wasteful number, since it uses less digits than its factorization.

189957181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612.

The product of its digits is 181440, while the sum is 49.

The square root of 189957181 is about 13782.4954561937. The cubic root of 189957181 is about 574.8465183299.

The spelling of 189957181 in words is "one hundred eighty-nine million, nine hundred fifty-seven thousand, one hundred eighty-one".