18764866 has 4 divisors (see below), whose sum is σ = 28147302. Its totient is φ = 9382432.

The previous prime is 18764843. The next prime is 18764887. The reversal of 18764866 is 66846781.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66846781 = 797 ⋅83873.

It can be written as a sum of positive squares in only one way, i.e., 16982641 + 1782225 = 4121^2 + 1335^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4691215 + ... + 4691218.

Almost surely, 2^18764866 is an apocalyptic number.

18764866 is a deficient number, since it is larger than the sum of its proper divisors (9382436).

18764866 is an equidigital number, since it uses as much as digits as its factorization.

18764866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9382435.

The product of its digits is 387072, while the sum is 46.

The square root of 18764866 is about 4331.8432566288. The cubic root of 18764866 is about 265.7348347805.

The spelling of 18764866 in words is "eighteen million, seven hundred sixty-four thousand, eight hundred sixty-six".