19963980 has 72 divisors (see below), whose sum is σ = 60972912. Its totient is φ = 5287296.

The previous prime is 19963973. The next prime is 19963981. The reversal of 19963980 is 8936991.

19963980 is a `hidden beast` number, since 1 + 9 + 9 + 639 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (19963981) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35179 + ... + 35741.

It is an arithmetic number, because the mean of its divisors is an integer number (846846).

Almost surely, 2^19963980 is an apocalyptic number.

19963980 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 19963980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30486456).

19963980 is an abundant number, since it is smaller than the sum of its proper divisors (41008932).

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

19963980 is a wasteful number, since it uses less digits than its factorization.

19963980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 775 (or 770 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 19963980 is about 4468.1069817094. The cubic root of 19963980 is about 271.2787081963.

The spelling of 19963980 in words is "nineteen million, nine hundred sixty-three thousand, nine hundred eighty".