20159988 has 48 divisors (see below), whose sum is σ = 51240000. Its totient is φ = 6144768.

The previous prime is 20159957. The next prime is 20160001. The reversal of 20159988 is 88995102.

It is a happy number.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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, 5088 + ... + 8136.

It is an arithmetic number, because the mean of its divisors is an integer number (1067500).

Almost surely, 2^20159988 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20159988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25620000).

20159988 is an abundant number, since it is smaller than the sum of its proper divisors (31080012).

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

20159988 is a wasteful number, since it uses less digits than its factorization.

20159988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3104 (or 3102 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 20159988 is about 4489.9875278223. The cubic root of 20159988 is about 272.1636306374.

The spelling of 20159988 in words is "twenty million, one hundred fifty-nine thousand, nine hundred eighty-eight".