19813040 has 40 divisors (see below), whose sum is σ = 49611408. Its totient is φ = 7315200.

The previous prime is 19813033. The next prime is 19813049. The reversal of 19813040 is 4031891.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-3 number, since 3×19813040³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is not an unprimeable number, because it can be changed into a prime (19813049) 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 7 ways as a sum of consecutive naturals, for example, 8486 + ... + 10565.

Almost surely, 2^19813040 is an apocalyptic number.

19813040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19813040 is an abundant number, since it is smaller than the sum of its proper divisors (29798368).

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

19813040 is a wasteful number, since it uses less digits than its factorization.

19813040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19077 (or 19071 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 19813040 is about 4451.1841121212. The cubic root of 19813040 is about 270.5932998051.

The spelling of 19813040 in words is "nineteen million, eight hundred thirteen thousand, forty".