20150666 has 4 divisors (see below), whose sum is σ = 30226002. Its totient is φ = 10075332.

The previous prime is 20150633. The next prime is 20150677. The reversal of 20150666 is 66605102.

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

It can be written as a sum of positive squares in only one way, i.e., 14250625 + 5900041 = 3775^2 + 2429^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5037665 + ... + 5037668.

Almost surely, 2^20150666 is an apocalyptic number.

20150666 is a deficient number, since it is larger than the sum of its proper divisors (10075336).

20150666 is a wasteful number, since it uses less digits than its factorization.

20150666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10075335.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 20150666 is about 4488.9493202753. The cubic root of 20150666 is about 272.1216745853.

Adding to 20150666 its reverse (66605102), we get a palindrome (86755768).

The spelling of 20150666 in words is "twenty million, one hundred fifty thousand, six hundred sixty-six".