20971537548 has 96 divisors (see below), whose sum is σ = 53058194112. Its totient is φ = 6408806400.

The previous prime is 20971537547. The next prime is 20971537549. The reversal of 20971537548 is 84573517902.

It is an interprime number because it is at equal distance from previous prime (20971537547) and next prime (20971537549).

It is a self number, because there is not a number n which added to its sum of digits gives 20971537548.

It is not an unprimeable number, because it can be changed into a prime (20971537547) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27557488 + ... + 27558248.

It is an arithmetic number, because the mean of its divisors is an integer number (552689522).

Almost surely, 2^20971537548 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 20971537548, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26529097056).

20971537548 is an abundant number, since it is smaller than the sum of its proper divisors (32086656564).

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

20971537548 is a wasteful number, since it uses less digits than its factorization.

20971537548 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1755 (or 1753 counting only the distinct ones).

The product of its (nonzero) digits is 2116800, while the sum is 51.

The spelling of 20971537548 in words is "twenty billion, nine hundred seventy-one million, five hundred thirty-seven thousand, five hundred forty-eight".