19899880 has 192 divisors, whose sum is σ = 62052480. Its totient is φ = 5644800.

The previous prime is 19899839. The next prime is 19899881. The reversal of 19899880 is 8899891.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (19899881) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 280245 + ... + 280315.

It is an arithmetic number, because the mean of its divisors is an integer number (323190).

Almost surely, 2^19899880 is an apocalyptic number.

19899880 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 19899880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31026240).

19899880 is an abundant number, since it is smaller than the sum of its proper divisors (42152600).

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

19899880 is a wasteful number, since it uses less digits than its factorization.

19899880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120 (or 109 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 52.

The square root of 19899880 is about 4460.9281545436. The cubic root of 19899880 is about 270.9880579152.

The spelling of 19899880 in words is "nineteen million, eight hundred ninety-nine thousand, eight hundred eighty".