19915428 has 24 divisors (see below), whose sum is σ = 50044288. Its totient is φ = 6127776.

The previous prime is 19915417. The next prime is 19915433. The reversal of 19915428 is 82451991.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

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, 63676 + ... + 63987.

Almost surely, 2^19915428 is an apocalyptic number.

It is an amenable number.

19915428 is an abundant number, since it is smaller than the sum of its proper divisors (30128860).

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

19915428 is a wasteful number, since it uses less digits than its factorization.

19915428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127683 (or 127681 counting only the distinct ones).

The product of its digits is 25920, while the sum is 39.

The square root of 19915428 is about 4462.6705009445. The cubic root of 19915428 is about 271.0586148817.

The spelling of 19915428 in words is "nineteen million, nine hundred fifteen thousand, four hundred twenty-eight".