19197840 has 80 divisors (see below), whose sum is σ = 60996096. Its totient is φ = 4992000.

The previous prime is 19197839. The next prime is 19197853. The reversal of 19197840 is 4879191.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

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, 8865 + ... + 10815.

Almost surely, 2^19197840 is an apocalyptic number.

19197840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19197840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30498048).

19197840 is an abundant number, since it is smaller than the sum of its proper divisors (41798256).

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

19197840 is a wasteful number, since it uses less digits than its factorization.

19197840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2008 (or 2002 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 39.

The square root of 19197840 is about 4381.5339779579. The cubic root of 19197840 is about 267.7631381620.

The spelling of 19197840 in words is "nineteen million, one hundred ninety-seven thousand, eight hundred forty".