20530311888 has 80 divisors (see below), whose sum is σ = 55832676480. Its totient is φ = 6487928832.

The previous prime is 20530311887. The next prime is 20530311899. The reversal of 20530311888 is 88811303502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20530311887) 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, 42468 + ... + 207036.

It is an arithmetic number, because the mean of its divisors is an integer number (697908456).

Almost surely, 2^20530311888 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 20530311888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27916338240).

20530311888 is an abundant number, since it is smaller than the sum of its proper divisors (35302364592).

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

20530311888 is a wasteful number, since it uses less digits than its factorization.

20530311888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164716 (or 164710 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 39.

The spelling of 20530311888 in words is "twenty billion, five hundred thirty million, three hundred eleven thousand, eight hundred eighty-eight".