217251872053 has 2 divisors, whose sum is σ = 217251872054. Its totient is φ = 217251872052.

The previous prime is 217251872023. The next prime is 217251872059. The reversal of 217251872053 is 350278152712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 211165063729 + 6086808324 = 459527^2 + 78018^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217251872053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217251872059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108625936026 + 108625936027.

It is an arithmetic number, because the mean of its divisors is an integer number (108625936027).

Almost surely, 2^217251872053 is an apocalyptic number.

It is an amenable number.

217251872053 is a deficient number, since it is larger than the sum of its proper divisors (1).

217251872053 is an equidigital number, since it uses as much as digits as its factorization.

217251872053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 235200, while the sum is 43.

The spelling of 217251872053 in words is "two hundred seventeen billion, two hundred fifty-one million, eight hundred seventy-two thousand, fifty-three".