20187817488 has 80 divisors (see below), whose sum is σ = 58066104960. Its totient is φ = 6715384704.

The previous prime is 20187817409. The next prime is 20187817499. The reversal of 20187817488 is 88471878102.

It is a happy number.

20187817488 is a `hidden beast` number, since 2 + 0 + 1 + 87 + 81 + 7 + 488 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

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, 162406 + ... + 258362.

It is an arithmetic number, because the mean of its divisors is an integer number (725826312).

Almost surely, 2^20187817488 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 20187817488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29033052480).

20187817488 is an abundant number, since it is smaller than the sum of its proper divisors (37878287472).

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

20187817488 is a wasteful number, since it uses less digits than its factorization.

20187817488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96461 (or 96449 counting only the distinct ones).

The product of its (nonzero) digits is 1605632, while the sum is 54.

The spelling of 20187817488 in words is "twenty billion, one hundred eighty-seven million, eight hundred seventeen thousand, four hundred eighty-eight".