20752775257 has 4 divisors (see below), whose sum is σ = 20753092836. Its totient is φ = 20752457680.

The previous prime is 20752775237. The next prime is 20752775287. The reversal of 20752775257 is 75257725702.

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 12211134016 + 8541641241 = 110504^2 + 92421^2 .

It is a cyclic number.

It is not a de Polignac number, because 20752775257 - 2¹⁵ = 20752742489 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20752775257.

It is not an unprimeable number, because it can be changed into a prime (20752775237) 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, 20794 + ... + 204787.

It is an arithmetic number, because the mean of its divisors is an integer number (5188273209).

Almost surely, 2^20752775257 is an apocalyptic number.

It is an amenable number.

20752775257 is a deficient number, since it is larger than the sum of its proper divisors (317579).

20752775257 is an equidigital number, since it uses as much as digits as its factorization.

20752775257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317578.

The product of its (nonzero) digits is 2401000, while the sum is 49.

The spelling of 20752775257 in words is "twenty billion, seven hundred fifty-two million, seven hundred seventy-five thousand, two hundred fifty-seven".