18949805 has 16 divisors (see below), whose sum is σ = 26193024. Its totient is φ = 12891840.

The previous prime is 18949793. The next prime is 18949817. The reversal of 18949805 is 50894981.

It is an interprime number because it is at equal distance from previous prime (18949793) and next prime (18949817).

It is not a de Polignac number, because 18949805 - 2⁶ = 18949741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2519 + ... + 6651.

It is an arithmetic number, because the mean of its divisors is an integer number (1637064).

Almost surely, 2^18949805 is an apocalyptic number.

It is an amenable number.

18949805 is a deficient number, since it is larger than the sum of its proper divisors (7243219).

18949805 is a wasteful number, since it uses less digits than its factorization.

18949805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4276.

The product of its (nonzero) digits is 103680, while the sum is 44.

The square root of 18949805 is about 4353.1373743543. The cubic root of 18949805 is about 266.6049744441.

It can be divided in two parts, 189 and 49805, that added together give a palindrome (49994).

The spelling of 18949805 in words is "eighteen million, nine hundred forty-nine thousand, eight hundred five".