189626981 has 4 divisors (see below), whose sum is σ = 190233132. Its totient is φ = 189020832.

The previous prime is 189626971. The next prime is 189626989.

It is a happy number.

189626981 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 41396356 + 148230625 = 6434^2 + 12175^2 .

It is a cyclic number.

It is not a de Polignac number, because 189626981 - 2¹⁰ = 189625957 is a prime.

It is a super-4 number, since 4×189626981⁴ (a number of 34 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189626989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 302606 + ... + 303231.

It is an arithmetic number, because the mean of its divisors is an integer number (47558283).

Almost surely, 2^189626981 is an apocalyptic number.

It is an amenable number.

189626981 is a deficient number, since it is larger than the sum of its proper divisors (606151).

189626981 is an equidigital number, since it uses as much as digits as its factorization.

189626981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606150.

The product of its digits is 373248, while the sum is 50.

The square root of 189626981 is about 13770.5112831732. The cubic root of 189626981 is about 574.5132425015.

The spelling of 189626981 in words is "one hundred eighty-nine million, six hundred twenty-six thousand, nine hundred eighty-one".