20266521055457 has 4 divisors (see below), whose sum is σ = 20266536350100. Its totient is φ = 20266505760816.

The previous prime is 20266521055453. The next prime is 20266521055481. The reversal of 20266521055457 is 75455012566202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17280948305296 + 2985572750161 = 4157036^2 + 1727881^2 .

It is a cyclic number.

It is not a de Polignac number, because 20266521055457 - 2² = 20266521055453 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20266521055453) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5449082 + ... + 8380067.

It is an arithmetic number, because the mean of its divisors is an integer number (5066634087525).

Almost surely, 2^{20266521055457} is an apocalyptic number.

It is an amenable number.

20266521055457 is a deficient number, since it is larger than the sum of its proper divisors (15294643).

20266521055457 is a wasteful number, since it uses less digits than its factorization.

20266521055457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15294642.

The product of its (nonzero) digits is 5040000, while the sum is 50.

The spelling of 20266521055457 in words is "twenty trillion, two hundred sixty-six billion, five hundred twenty-one million, fifty-five thousand, four hundred fifty-seven".