19640880 has 200 divisors, whose sum is σ = 78140832. Its totient is φ = 4478976.

The previous prime is 19640879. The next prime is 19640893. The reversal of 19640880 is 8804691.

It is a happy number.

19640880 is a `hidden beast` number, since 1 + 9 + 640 + 8 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 45144 + ... + 45576.

Almost surely, 2^19640880 is an apocalyptic number.

19640880 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 19640880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39070416).

19640880 is an abundant number, since it is smaller than the sum of its proper divisors (58499952).

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

19640880 is a wasteful number, since it uses less digits than its factorization.

19640880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465 (or 450 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 19640880 is about 4431.8032447301. The cubic root of 19640880 is about 269.8072698664.

The spelling of 19640880 in words is "nineteen million, six hundred forty thousand, eight hundred eighty".