18697985450 has 24 divisors (see below), whose sum is σ = 34896977388. Its totient is φ = 7453662080.

The previous prime is 18697985437. The next prime is 18697985461. The reversal of 18697985450 is 5458979681.

It can be written as a sum of positive squares in 6 ways, for example, as 6893814841 + 11804170609 = 83029^2 + 108647^2 .

It is a super-2 number, since 2×18697985450² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 623507 + ... + 652806.

Almost surely, 2^18697985450 is an apocalyptic number.

18697985450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18697985450 is a deficient number, since it is larger than the sum of its proper divisors (16198991938).

18697985450 is a wasteful number, since it uses less digits than its factorization.

18697985450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1276618 (or 1276613 counting only the distinct ones).

The product of its (nonzero) digits is 21772800, while the sum is 62.

The spelling of 18697985450 in words is "eighteen billion, six hundred ninety-seven million, nine hundred eighty-five thousand, four hundred fifty".