18946649 has 4 divisors (see below), whose sum is σ = 19186560. Its totient is φ = 18706740.

The previous prime is 18946643. The next prime is 18946663. The reversal of 18946649 is 94664981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18946649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18946643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 119837 + ... + 119994.

It is an arithmetic number, because the mean of its divisors is an integer number (4796640).

Almost surely, 2^18946649 is an apocalyptic number.

It is an amenable number.

18946649 is a deficient number, since it is larger than the sum of its proper divisors (239911).

18946649 is an equidigital number, since it uses as much as digits as its factorization.

18946649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239910.

The product of its digits is 373248, while the sum is 47.

The square root of 18946649 is about 4352.7748620851. The cubic root of 18946649 is about 266.5901730251.

The spelling of 18946649 in words is "eighteen million, nine hundred forty-six thousand, six hundred forty-nine".