19800064 has 28 divisors (see below), whose sum is σ = 39614094. Its totient is φ = 9895936.

The previous prime is 19799993. The next prime is 19800083. The reversal of 19800064 is 46000891.

It can be written as a sum of positive squares in only one way, i.e., 11505664 + 8294400 = 3392^2 + 2880^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6984 + ... + 9400.

Almost surely, 2^19800064 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19800064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19807047).

19800064 is an abundant number, since it is smaller than the sum of its proper divisors (19814030).

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

19800064 is an frugal number, since it uses more digits than its factorization.

19800064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2443 (or 2419 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 19800064 is about 4449.7262837168. The cubic root of 19800064 is about 270.5342143836.

The spelling of 19800064 in words is "nineteen million, eight hundred thousand, sixty-four".