19981836 has 48 divisors (see below), whose sum is σ = 59207680. Its totient is φ = 5708880.

The previous prime is 19981807. The next prime is 19981867. The reversal of 19981836 is 63818991.

It is a junction number, because it is equal to n+sod(n) for n = 19981791 and 19981800.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12460 + ... + 13971.

Almost surely, 2^19981836 is an apocalyptic number.

It is an amenable number.

19981836 is an abundant number, since it is smaller than the sum of its proper divisors (39225844).

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

19981836 is a wasteful number, since it uses less digits than its factorization.

19981836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26451 (or 26443 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 19981836 is about 4470.1046967605. The cubic root of 19981836 is about 271.3595623007.

The spelling of 19981836 in words is "nineteen million, nine hundred eighty-one thousand, eight hundred thirty-six".