18696978 has 12 divisors (see below), whose sum is σ = 40510158. Its totient is φ = 6232320.

The previous prime is 18696949. The next prime is 18696983. The reversal of 18696978 is 87969681.

It can be written as a sum of positive squares in only one way, i.e., 18688329 + 8649 = 4323^2 + 93^2 .

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, 519343 + ... + 519378.

Almost surely, 2^18696978 is an apocalyptic number.

18696978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18696978 is an abundant number, since it is smaller than the sum of its proper divisors (21813180).

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

18696978 is a wasteful number, since it uses less digits than its factorization.

18696978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1038729 (or 1038726 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 54.

The square root of 18696978 is about 4324.0002312673. Note that the first 3 decimals coincide. The cubic root of 18696978 is about 265.4139868418.

The spelling of 18696978 in words is "eighteen million, six hundred ninety-six thousand, nine hundred seventy-eight".