21755081750 has 48 divisors (see below), whose sum is σ = 41743851552. Its totient is φ = 8489624000.

The previous prime is 21755081743. The next prime is 21755081851. The reversal of 21755081750 is 5718055712.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a junction number, because it is equal to n+sod(n) for n = 21755081698 and 21755081707.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 394367 + ... + 446133.

It is an arithmetic number, because the mean of its divisors is an integer number (869663574).

Almost surely, 2^21755081750 is an apocalyptic number.

21755081750 is a deficient number, since it is larger than the sum of its proper divisors (19988769802).

21755081750 is an equidigital number, since it uses as much as digits as its factorization.

21755081750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51866 (or 51815 counting only the distinct ones).

The product of its (nonzero) digits is 98000, while the sum is 41.

The spelling of 21755081750 in words is "twenty-one billion, seven hundred fifty-five million, eighty-one thousand, seven hundred fifty".