19897900 has 36 divisors (see below), whose sum is σ = 47106360. Its totient is φ = 7235200.

The previous prime is 19897859. The next prime is 19897903. The reversal of 19897900 is 979891.

It is not an unprimeable number, because it can be changed into a prime (19897903) 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, 7945 + ... + 10144.

It is an arithmetic number, because the mean of its divisors is an integer number (1308510).

Almost surely, 2^19897900 is an apocalyptic number.

19897900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19897900 is an abundant number, since it is smaller than the sum of its proper divisors (27208460).

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

19897900 is a wasteful number, since it uses less digits than its factorization.

19897900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18114 (or 18107 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 19897900 is about 4460.7062221133. The cubic root of 19897900 is about 270.9790700193.

It can be divided in two parts, 1989 and 7900, that added together give a palindrome (9889).

The spelling of 19897900 in words is "nineteen million, eight hundred ninety-seven thousand, nine hundred".