18697861784 has 48 divisors (see below), whose sum is σ = 40795435800. Its totient is φ = 8010793728.

The previous prime is 18697861781. The next prime is 18697861801. The reversal of 18697861784 is 48716879681.

It is a super-2 number, since 2×18697861784² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18697861784.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18697861781) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1695392 + ... + 1706384.

Almost surely, 2^18697861784 is an apocalyptic number.

18697861784 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

18697861784 is an abundant number, since it is smaller than the sum of its proper divisors (22097574016).

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

18697861784 is a wasteful number, since it uses less digits than its factorization.

18697861784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15352 (or 15341 counting only the distinct ones).

The product of its digits is 32514048, while the sum is 65.

The spelling of 18697861784 in words is "eighteen billion, six hundred ninety-seven million, eight hundred sixty-one thousand, seven hundred eighty-four".