20731845754577 has 8 divisors (see below), whose sum is σ = 21068780304936. Its totient is φ = 20396341924992.

The previous prime is 20731845754549. The next prime is 20731845754589. The reversal of 20731845754577 is 77545754813702.

It can be written as a sum of positive squares in 4 ways, for example, as 10783631416336 + 9948214338241 = 3283844^2 + 3154079^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20731845754577 - 2¹⁶ = 20731845689041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20731845754547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 357650978 + ... + 357708939.

It is an arithmetic number, because the mean of its divisors is an integer number (2633597538117).

Almost surely, 2^{20731845754577} is an apocalyptic number.

It is an amenable number.

20731845754577 is a deficient number, since it is larger than the sum of its proper divisors (336934550359).

20731845754577 is an equidigital number, since it uses as much as digits as its factorization.

20731845754577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 715360387.

The product of its (nonzero) digits is 230496000, while the sum is 65.

The spelling of 20731845754577 in words is "twenty trillion, seven hundred thirty-one billion, eight hundred forty-five million, seven hundred fifty-four thousand, five hundred seventy-seven".