19804540 has 24 divisors (see below), whose sum is σ = 47531232. Its totient is φ = 6790080.

The previous prime is 19804529. The next prime is 19804549. The reversal of 19804540 is 4540891.

It is a happy number.

It is a super-2 number, since 2×19804540² = 784439609223200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19804549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70591 + ... + 70870.

It is an arithmetic number, because the mean of its divisors is an integer number (1980468).

Almost surely, 2^19804540 is an apocalyptic number.

19804540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19804540 is an abundant number, since it is smaller than the sum of its proper divisors (27726692).

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

19804540 is a wasteful number, since it uses less digits than its factorization.

19804540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141477 (or 141475 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 19804540 is about 4450.2292075802. The cubic root of 19804540 is about 270.5545984912.

The spelling of 19804540 in words is "nineteen million, eight hundred four thousand, five hundred forty".