20491610418756 has 81 divisors (see below), whose sum is σ = 53789669488191. Its totient is φ = 6830292360888.

The previous prime is 20491610418743. The next prime is 20491610418767. The reversal of 20491610418756 is 65781401619402.

The square root of 20491610418756 is 4526766.

It is a perfect power (a square), and thus also a powerful number.

20491610418756 is a `hidden beast` number, since 2 + 0 + 4 + 9 + 1 + 610 + 4 + 18 + 7 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (81).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 733322121 + ... + 733350063.

Almost surely, 2^{20491610418756} is an apocalyptic number.

20491610418756 is the 4526766-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20491610418756

20491610418756 is an abundant number, since it is smaller than the sum of its proper divisors (33298059069435).

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

20491610418756 is an frugal number, since it uses more digits than its factorization.

20491610418756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55914 (or 27948 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 20491610418756 in words is "twenty trillion, four hundred ninety-one billion, six hundred ten million, four hundred eighteen thousand, seven hundred fifty-six".