18781012 has 24 divisors (see below), whose sum is σ = 33780096. Its totient is φ = 9132288.

The previous prime is 18781001. The next prime is 18781013. The reversal of 18781012 is 21018781.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18781013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53028 + ... + 53380.

It is an arithmetic number, because the mean of its divisors is an integer number (1407504).

Almost surely, 2^18781012 is an apocalyptic number.

It is an amenable number.

18781012 is a deficient number, since it is larger than the sum of its proper divisors (14999084).

18781012 is a wasteful number, since it uses less digits than its factorization.

18781012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 687 (or 685 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 28.

The square root of 18781012 is about 4333.7064967531. The cubic root of 18781012 is about 265.8110290300.

Adding to 18781012 its reverse (21018781), we get a palindrome (39799793).

The spelling of 18781012 in words is "eighteen million, seven hundred eighty-one thousand, twelve".