18961308 has 18 divisors (see below), whose sum is σ = 47930064. Its totient is φ = 6320424.

The previous prime is 18961289. The next prime is 18961321. The reversal of 18961308 is 80316981.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 526703 = 18961308 / (1 + 8 + 9 + 6 + 1 + 3 + 0 + 8).

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 5 ways as a sum of consecutive naturals, for example, 263316 + ... + 263387.

Almost surely, 2^18961308 is an apocalyptic number.

18961308 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

18961308 is an abundant number, since it is smaller than the sum of its proper divisors (28968756).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18961308 is a wasteful number, since it uses less digits than its factorization.

18961308 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526713 (or 526708 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 18961308 is about 4354.4584048995. The cubic root of 18961308 is about 266.6589088021.

The spelling of 18961308 in words is "eighteen million, nine hundred sixty-one thousand, three hundred eight".