21585700848 has 40 divisors (see below), whose sum is σ = 57685928400. Its totient is φ = 6947121664.

The previous prime is 21585700847. The next prime is 21585700867. The reversal of 21585700848 is 84800758512.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 21585700797 and 21585700806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21585700847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7752093 + ... + 7754876.

It is an arithmetic number, because the mean of its divisors is an integer number (1442148210).

Almost surely, 2^21585700848 is an apocalyptic number.

It is an amenable number.

21585700848 is an abundant number, since it is smaller than the sum of its proper divisors (36100227552).

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

21585700848 is a wasteful number, since it uses less digits than its factorization.

21585700848 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15507009 (or 15507003 counting only the distinct ones).

The product of its (nonzero) digits is 716800, while the sum is 48.

The spelling of 21585700848 in words is "twenty-one billion, five hundred eighty-five million, seven hundred thousand, eight hundred forty-eight".