19939920 has 320 divisors, whose sum is σ = 83994624. Its totient is φ = 3778560.

The previous prime is 19939901. The next prime is 19939943. The reversal of 19939920 is 2993991.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 240199 + ... + 240281.

Almost surely, 2^19939920 is an apocalyptic number.

19939920 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 19939920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41997312).

19939920 is an abundant number, since it is smaller than the sum of its proper divisors (64054704).

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

19939920 is a wasteful number, since it uses less digits than its factorization.

19939920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 39366, while the sum is 42.

The square root of 19939920 is about 4465.4137546257. The cubic root of 19939920 is about 271.1696853543.

It can be divided in two parts, 19 and 939920, that added together give a palindrome (939939).

The spelling of 19939920 in words is "nineteen million, nine hundred thirty-nine thousand, nine hundred twenty".