19988490 has 32 divisors (see below), whose sum is σ = 49522176. Its totient is φ = 5158080.

The previous prime is 19988477. The next prime is 19988491. The reversal of 19988490 is 9488991.

It is not an unprimeable number, because it can be changed into a prime (19988491) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9817 + ... + 11676.

It is an arithmetic number, because the mean of its divisors is an integer number (1547568).

Almost surely, 2^19988490 is an apocalyptic number.

19988490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19988490 is an abundant number, since it is smaller than the sum of its proper divisors (29533686).

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

19988490 is a wasteful number, since it uses less digits than its factorization.

19988490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21534.

The product of its (nonzero) digits is 186624, while the sum is 48.

The square root of 19988490 is about 4470.8489126787. The cubic root of 19988490 is about 271.3896800893.

The spelling of 19988490 in words is "nineteen million, nine hundred eighty-eight thousand, four hundred ninety".