19928340 has 72 divisors (see below), whose sum is σ = 63641760. Its totient is φ = 5033664.

The previous prime is 19928339. The next prime is 19928347. The reversal of 19928340 is 4382991.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 19928295 and 19928304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19928347) 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, 507 + ... + 6333.

Almost surely, 2^19928340 is an apocalyptic number.

19928340 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 19928340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31820880).

19928340 is an abundant number, since it is smaller than the sum of its proper divisors (43713420).

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

19928340 is a wasteful number, since it uses less digits than its factorization.

19928340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5861 (or 5856 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 19928340 is about 4464.1169339523. The cubic root of 19928340 is about 271.1171817497.

The spelling of 19928340 in words is "nineteen million, nine hundred twenty-eight thousand, three hundred forty".