1980817664 has 144 divisors (see below), whose sum is σ = 4714085376. Its totient is φ = 812851200.

The previous prime is 1980817627. The next prime is 1980817687. The reversal of 1980817664 is 4667180891.

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, 10054814 + ... + 10055010.

It is an arithmetic number, because the mean of its divisors is an integer number (32736704).

Almost surely, 2^1980817664 is an apocalyptic number.

1980817664 is a gapful number since it is divisible by the number (14) 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 1980817664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2357042688).

1980817664 is an abundant number, since it is smaller than the sum of its proper divisors (2733267712).

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

1980817664 is a wasteful number, since it uses less digits than its factorization.

1980817664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432 (or 418 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 50.

The square root of 1980817664 is about 44506.3777901550. The cubic root of 1980817664 is about 1255.8800648186.

The spelling of 1980817664 in words is "one billion, nine hundred eighty million, eight hundred seventeen thousand, six hundred sixty-four".