19881030 has 64 divisors (see below), whose sum is σ = 54109440. Its totient is φ = 4634496.

The previous prime is 19881019. The next prime is 19881077. The reversal of 19881030 is 3018891.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 6069 + ... + 8751.

It is an arithmetic number, because the mean of its divisors is an integer number (845460).

Almost surely, 2^19881030 is an apocalyptic number.

19881030 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19881030, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27054720).

19881030 is an abundant number, since it is smaller than the sum of its proper divisors (34228410).

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

19881030 is a wasteful number, since it uses less digits than its factorization.

19881030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2725.

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 19881030 is about 4458.8148649613. The cubic root of 19881030 is about 270.9024671375.

The spelling of 19881030 in words is "nineteen million, eight hundred eighty-one thousand, thirty".