19909312 has 56 divisors (see below), whose sum is σ = 43342560. Its totient is φ = 9031680.

The previous prime is 19909303. The next prime is 19909361. The reversal of 19909312 is 21390991.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31237 + ... + 31867.

Almost surely, 2^19909312 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 19909312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21671280).

19909312 is an abundant number, since it is smaller than the sum of its proper divisors (23433248).

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

19909312 is a wasteful number, since it uses less digits than its factorization.

19909312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 679 counting only the distinct ones).

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 19909312 is about 4461.9852084022. The cubic root of 19909312 is about 271.0308648007.

The spelling of 19909312 in words is "nineteen million, nine hundred nine thousand, three hundred twelve".