21748667680 has 48 divisors (see below), whose sum is σ = 54085510080. Its totient is φ = 8241599232.

The previous prime is 21748667671. The next prime is 21748667683. The reversal of 21748667680 is 8676684712.

It is not an unprimeable number, because it can be changed into a prime (21748667683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3574044 + ... + 3580123.

It is an arithmetic number, because the mean of its divisors is an integer number (1126781460).

Almost surely, 2^21748667680 is an apocalyptic number.

21748667680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21748667680 is an abundant number, since it is smaller than the sum of its proper divisors (32336842400).

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

21748667680 is a wasteful number, since it uses less digits than its factorization.

21748667680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7154201 (or 7154193 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 55.

The spelling of 21748667680 in words is "twenty-one billion, seven hundred forty-eight million, six hundred sixty-seven thousand, six hundred eighty".