19990680 has 64 divisors (see below), whose sum is σ = 62588160. Its totient is φ = 5098368.

The previous prime is 19990673. The next prime is 19990687. The reversal of 19990680 is 8609991.

19990680 = T₉₂₀ + T₉₂₁ + ... + T₉₆₄.

It is an interprime number because it is at equal distance from previous prime (19990673) and next prime (19990687).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19990687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 862 + ... + 6381.

It is an arithmetic number, because the mean of its divisors is an integer number (977940).

Almost surely, 2^19990680 is an apocalyptic number.

19990680 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 19990680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31294080).

19990680 is an abundant number, since it is smaller than the sum of its proper divisors (42597480).

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

19990680 is a wasteful number, since it uses less digits than its factorization.

19990680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7280 (or 7276 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 42.

The square root of 19990680 is about 4471.0938258999. The cubic root of 19990680 is about 271.3995911547.

The spelling of 19990680 in words is "nineteen million, nine hundred ninety thousand, six hundred eighty".