21806591148 has 48 divisors (see below), whose sum is σ = 57602331360. Its totient is φ = 7131713472.

The previous prime is 21806591141. The next prime is 21806591207. The reversal of 21806591148 is 84119560812.

It is a happy number.

21806591148 is a `hidden beast` number, since 2 + 18 + 0 + 6 + 591 + 1 + 48 = 666.

It is not an unprimeable number, because it can be changed into a prime (21806591141) 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, 1899115 + ... + 1910562.

It is an arithmetic number, because the mean of its divisors is an integer number (1200048570).

Almost surely, 2^21806591148 is an apocalyptic number.

It is an amenable number.

21806591148 is an abundant number, since it is smaller than the sum of its proper divisors (35795740212).

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

21806591148 is a wasteful number, since it uses less digits than its factorization.

21806591148 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3809743 (or 3809735 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 45.

The spelling of 21806591148 in words is "twenty-one billion, eight hundred six million, five hundred ninety-one thousand, one hundred forty-eight".