38661866 has 4 divisors (see below), whose sum is σ = 57992802. Its totient is φ = 19330932.

The previous prime is 38661851. The next prime is 38661869. The reversal of 38661866 is 66816683.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66816683 = 7927 ⋅8429.

It can be written as a sum of positive squares in only one way, i.e., 26306641 + 12355225 = 5129^2 + 3515^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (38661869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9665465 + ... + 9665468.

Almost surely, 2^38661866 is an apocalyptic number.

38661866 is a deficient number, since it is larger than the sum of its proper divisors (19330936).

38661866 is a wasteful number, since it uses less digits than its factorization.

38661866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19330935.

The product of its digits is 248832, while the sum is 44.

The square root of 38661866 is about 6217.8666759589. The cubic root of 38661866 is about 338.1382264373.

The spelling of 38661866 in words is "thirty-eight million, six hundred sixty-one thousand, eight hundred sixty-six".