19930840 has 16 divisors (see below), whose sum is σ = 44844480. Its totient is φ = 7972320.

The previous prime is 19930787. The next prime is 19930843. The reversal of 19930840 is 4803991.

It is a junction number, because it is equal to n+sod(n) for n = 19930796 and 19930805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19930843) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 249096 + ... + 249175.

It is an arithmetic number, because the mean of its divisors is an integer number (2802780).

Almost surely, 2^19930840 is an apocalyptic number.

19930840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19930840 is an abundant number, since it is smaller than the sum of its proper divisors (24913640).

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

19930840 is a wasteful number, since it uses less digits than its factorization.

19930840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498282 (or 498278 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 19930840 is about 4464.3969357574. The cubic root of 19930840 is about 271.1285184459.

The spelling of 19930840 in words is "nineteen million, nine hundred thirty thousand, eight hundred forty".