15661066 has 8 divisors (see below), whose sum is σ = 23583780. Its totient is φ = 7799808.

The previous prime is 15661033. The next prime is 15661069. The reversal of 15661066 is 66016651.

It can be written as a sum of positive squares in 2 ways, for example, as 13905441 + 1755625 = 3729^2 + 1325^2 .

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

It is not an unprimeable number, because it can be changed into a prime (15661069) 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 3 ways as a sum of consecutive naturals, for example, 14721 + ... + 15748.

Almost surely, 2^15661066 is an apocalyptic number.

15661066 is a deficient number, since it is larger than the sum of its proper divisors (7922714).

15661066 is a wasteful number, since it uses less digits than its factorization.

15661066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30728.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 15661066 is about 3957.4064739422. The cubic root of 15661066 is about 250.1922041923.

The spelling of 15661066 in words is "fifteen million, six hundred sixty-one thousand, sixty-six".