661174989 has 8 divisors (see below), whose sum is σ = 890655360. Its totient is φ = 436238976.

The previous prime is 661174981. The next prime is 661174993. The reversal of 661174989 is 989471166.

It is a happy number.

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

It is not a de Polignac number, because 661174989 - 2³ = 661174981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661174981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1135749 + ... + 1136330.

It is an arithmetic number, because the mean of its divisors is an integer number (111331920).

Almost surely, 2^661174989 is an apocalyptic number.

It is an amenable number.

661174989 is a deficient number, since it is larger than the sum of its proper divisors (229480371).

661174989 is a wasteful number, since it uses less digits than its factorization.

661174989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2272179.

The product of its digits is 653184, while the sum is 51.

The square root of 661174989 is about 25713.3231807948. The cubic root of 661174989 is about 871.1751367891.

The spelling of 661174989 in words is "six hundred sixty-one million, one hundred seventy-four thousand, nine hundred eighty-nine".