21767608742928 has 320 divisors, whose sum is σ = 59409819671040. Its totient is φ = 6858246979584.

The previous prime is 21767608742881. The next prime is 21767608742963. The reversal of 21767608742928 is 82924780676712.

It is a Cunningham number, because it is equal to 4665577²-1.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8174091325 + ... + 8174093987.

It is an arithmetic number, because the mean of its divisors is an integer number (185655686472).

Almost surely, 2^{21767608742928} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21767608742928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29704909835520).

21767608742928 is an abundant number, since it is smaller than the sum of its proper divisors (37642210928112).

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

21767608742928 is a wasteful number, since it uses less digits than its factorization.

21767608742928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3346 (or 3340 counting only the distinct ones).

The product of its (nonzero) digits is 227598336, while the sum is 69.

The spelling of 21767608742928 in words is "twenty-one trillion, seven hundred sixty-seven billion, six hundred eight million, seven hundred forty-two thousand, nine hundred twenty-eight".