189868981 has 8 divisors (see below), whose sum is σ = 193221504. Its totient is φ = 186535440.

The previous prime is 189868969. The next prime is 189869011.

189868981 = 251² + 252² + ... + 836².

189868981 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 189868981 - 2¹⁷ = 189737909 is a prime.

It is a super-2 number, since 2×189868981² = 72100459891956722, 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 (189868901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16240 + ... + 25366.

It is an arithmetic number, because the mean of its divisors is an integer number (24152688).

Almost surely, 2^189868981 is an apocalyptic number.

It is an amenable number.

189868981 is a deficient number, since it is larger than the sum of its proper divisors (3352523).

189868981 is an equidigital number, since it uses as much as digits as its factorization.

189868981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9491.

The product of its digits is 1990656, while the sum is 58.

The square root of 189868981 is about 13779.2953738571. The cubic root of 189868981 is about 574.7575345708.

The spelling of 189868981 in words is "one hundred eighty-nine million, eight hundred sixty-eight thousand, nine hundred eighty-one".