21758306940 has 96 divisors (see below), whose sum is σ = 67773303360. Its totient is φ = 5795290368.

The previous prime is 21758306923. The next prime is 21758306959. The reversal of 21758306940 is 4960385712.

21758306940 is a `hidden beast` number, since 2 + 1 + 7 + 583 + 0 + 69 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 437002 + ... + 484238.

It is an arithmetic number, because the mean of its divisors is an integer number (705971910).

It is a 1-persistent number, because it is pandigital, but 2⋅21758306940 = 43516613880 is not.

Almost surely, 2^21758306940 is an apocalyptic number.

21758306940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21758306940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33886651680).

21758306940 is an abundant number, since it is smaller than the sum of its proper divisors (46014996420).

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

21758306940 is a wasteful number, since it uses less digits than its factorization.

21758306940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48108 (or 48100 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 21758306940 in words is "twenty-one billion, seven hundred fifty-eight million, three hundred six thousand, nine hundred forty".