19931982 has 16 divisors (see below), whose sum is σ = 45558912. Its totient is φ = 5694840.

The previous prime is 19931953. The next prime is 19931987. The reversal of 19931982 is 28913991.

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 474571 = 19931982 / (1 + 9 + 9 + 3 + 1 + 9 + 8 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19931987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 237244 + ... + 237327.

It is an arithmetic number, because the mean of its divisors is an integer number (2847432).

Almost surely, 2^19931982 is an apocalyptic number.

19931982 is an abundant number, since it is smaller than the sum of its proper divisors (25626930).

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

19931982 is a wasteful number, since it uses less digits than its factorization.

19931982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474583.

The product of its digits is 34992, while the sum is 42.

The square root of 19931982 is about 4464.5248347389. The cubic root of 19931982 is about 271.1336967334.

Subtracting 19931982 from its reverse (28913991), we obtain a square (8982009 = 2997²).

The spelling of 19931982 in words is "nineteen million, nine hundred thirty-one thousand, nine hundred eighty-two".