19881988 has 48 divisors (see below), whose sum is σ = 41174784. Its totient is φ = 8225280.

The previous prime is 19881973. The next prime is 19882003. The reversal of 19881988 is 88918891.

It is an interprime number because it is at equal distance from previous prime (19881973) and next prime (19882003).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145056 + ... + 145192.

It is an arithmetic number, because the mean of its divisors is an integer number (857808).

Almost surely, 2^19881988 is an apocalyptic number.

It is an amenable number.

19881988 is an abundant number, since it is smaller than the sum of its proper divisors (21292796).

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

19881988 is a wasteful number, since it uses less digits than its factorization.

19881988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292 (or 290 counting only the distinct ones).

The product of its digits is 331776, while the sum is 52.

The square root of 19881988 is about 4458.9222913166. The cubic root of 19881988 is about 270.9068183607.

The spelling of 19881988 in words is "nineteen million, eight hundred eighty-one thousand, nine hundred eighty-eight".