19915938 has 48 divisors (see below), whose sum is σ = 49585536. Its totient is φ = 5659200.

The previous prime is 19915897. The next prime is 19915949. The reversal of 19915938 is 83951991.

It is a junction number, because it is equal to n+sod(n) for n = 19915893 and 19915902.

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 23 ways as a sum of consecutive naturals, for example, 32838 + ... + 33438.

It is an arithmetic number, because the mean of its divisors is an integer number (1033032).

Almost surely, 2^19915938 is an apocalyptic number.

19915938 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19915938, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24792768).

19915938 is an abundant number, since it is smaller than the sum of its proper divisors (29669598).

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

19915938 is a wasteful number, since it uses less digits than its factorization.

19915938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879 (or 876 counting only the distinct ones).

The product of its digits is 87480, while the sum is 45.

The square root of 19915938 is about 4462.7276412526. The cubic root of 19915938 is about 271.0609286442.

The spelling of 19915938 in words is "nineteen million, nine hundred fifteen thousand, nine hundred thirty-eight".