19979988 has 24 divisors (see below), whose sum is σ = 53280192. Its totient is φ = 5708544.

The previous prime is 19979987. The next prime is 19980019. The reversal of 19979988 is 88997991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19979987) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 118845 + ... + 119012.

It is an arithmetic number, because the mean of its divisors is an integer number (2220008).

Almost surely, 2^19979988 is an apocalyptic number.

It is an amenable number.

19979988 is an abundant number, since it is smaller than the sum of its proper divisors (33300204).

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

19979988 is a wasteful number, since it uses less digits than its factorization.

19979988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237871 (or 237869 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 60.

The square root of 19979988 is about 4469.8979854131. The cubic root of 19979988 is about 271.3511965707.

The spelling of 19979988 in words is "nineteen million, nine hundred seventy-nine thousand, nine hundred eighty-eight".