19980780 has 96 divisors (see below), whose sum is σ = 62415360. Its totient is φ = 4746240.

The previous prime is 19980743. The next prime is 19980791. The reversal of 19980780 is 8708991.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18865 + ... + 19895.

It is an arithmetic number, because the mean of its divisors is an integer number (650160).

Almost surely, 2^19980780 is an apocalyptic number.

19980780 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 19980780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31207680).

19980780 is an abundant number, since it is smaller than the sum of its proper divisors (42434580).

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

19980780 is a wasteful number, since it uses less digits than its factorization.

19980780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1079 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 42.

The square root of 19980780 is about 4469.9865771611. The cubic root of 19980780 is about 271.3547819467.

The spelling of 19980780 in words is "nineteen million, nine hundred eighty thousand, seven hundred eighty".