19979520 has 216 divisors, whose sum is σ = 71768928. Its totient is φ = 4730880.

The previous prime is 19979503. The next prime is 19979527. The reversal of 19979520 is 2597991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19979527) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 464619 + ... + 464661.

Almost surely, 2^19979520 is an apocalyptic number.

19979520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19979520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35884464).

19979520 is an abundant number, since it is smaller than the sum of its proper divisors (51789408).

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

19979520 is a wasteful number, since it uses less digits than its factorization.

19979520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 51030, while the sum is 42.

The square root of 19979520 is about 4469.8456349185. The cubic root of 19979520 is about 271.3490778949.

The spelling of 19979520 in words is "nineteen million, nine hundred seventy-nine thousand, five hundred twenty".