19891960 has 64 divisors (see below), whose sum is σ = 49805280. Its totient is φ = 7088640.

The previous prime is 19891939. The next prime is 19891961. The reversal of 19891960 is 6919891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19891961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22894 + ... + 23746.

Almost surely, 2^19891960 is an apocalyptic number.

19891960 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 19891960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24902640).

19891960 is an abundant number, since it is smaller than the sum of its proper divisors (29913320).

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

19891960 is a wasteful number, since it uses less digits than its factorization.

19891960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 928 (or 924 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 43.

The square root of 19891960 is about 4460.0403585618. The cubic root of 19891960 is about 270.9521027535.

The spelling of 19891960 in words is "nineteen million, eight hundred ninety-one thousand, nine hundred sixty".