21571377548 has 48 divisors (see below), whose sum is σ = 44869816320. Its totient is φ = 8881119936.

The previous prime is 21571377533. The next prime is 21571377577. The reversal of 21571377548 is 84577317512.

It is a junction number, because it is equal to n+sod(n) for n = 21571377496 and 21571377505.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49940 + ... + 213627.

It is an arithmetic number, because the mean of its divisors is an integer number (934787840).

Almost surely, 2^21571377548 is an apocalyptic number.

21571377548 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21571377548 is an abundant number, since it is smaller than the sum of its proper divisors (23298438772).

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

21571377548 is a wasteful number, since it uses less digits than its factorization.

21571377548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263694 (or 263692 counting only the distinct ones).

The product of its digits is 1646400, while the sum is 50.

The spelling of 21571377548 in words is "twenty-one billion, five hundred seventy-one million, three hundred seventy-seven thousand, five hundred forty-eight".