19940388 has 96 divisors (see below), whose sum is σ = 54302976. Its totient is φ = 5640192.

The previous prime is 19940383. The next prime is 19940411. The reversal of 19940388 is 88304991.

It is not an unprimeable number, because it can be changed into a prime (19940383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 193545 + ... + 193647.

It is an arithmetic number, because the mean of its divisors is an integer number (565656).

Almost surely, 2^19940388 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19940388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27151488).

19940388 is an abundant number, since it is smaller than the sum of its proper divisors (34362588).

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

19940388 is a wasteful number, since it uses less digits than its factorization.

19940388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 211 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 19940388 is about 4465.4661570770. The cubic root of 19940388 is about 271.1718068342.

The spelling of 19940388 in words is "nineteen million, nine hundred forty thousand, three hundred eighty-eight".