19720408 has 32 divisors (see below), whose sum is σ = 40219200. Its totient is φ = 9027072.

The previous prime is 19720403. The next prime is 19720447. The reversal of 19720408 is 80402791.

It is a self number, because there is not a number n which added to its sum of digits gives 19720408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19720403) 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, 3073 + ... + 6991.

It is an arithmetic number, because the mean of its divisors is an integer number (1256850).

Almost surely, 2^19720408 is an apocalyptic number.

It is an amenable number.

19720408 is an abundant number, since it is smaller than the sum of its proper divisors (20498792).

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

19720408 is a wasteful number, since it uses less digits than its factorization.

19720408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3979 (or 3975 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 19720408 is about 4440.7666004869. The cubic root of 19720408 is about 270.1709388511.

The spelling of 19720408 in words is "nineteen million, seven hundred twenty thousand, four hundred eight".