19904340 has 24 divisors (see below), whose sum is σ = 55732320. Its totient is φ = 5307808.

The previous prime is 19904333. The next prime is 19904341. The reversal of 19904340 is 4340991.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 19904298 and 19904307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19904341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 165810 + ... + 165929.

It is an arithmetic number, because the mean of its divisors is an integer number (2322180).

Almost surely, 2^19904340 is an apocalyptic number.

19904340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19904340 is an abundant number, since it is smaller than the sum of its proper divisors (35827980).

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

19904340 is a wasteful number, since it uses less digits than its factorization.

19904340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331751 (or 331749 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 19904340 is about 4461.4280225058. The cubic root of 19904340 is about 271.0083011940.

The spelling of 19904340 in words is "nineteen million, nine hundred four thousand, three hundred forty".