2251036721173 has 2 divisors, whose sum is σ = 2251036721174. Its totient is φ = 2251036721172.

The previous prime is 2251036721123. The next prime is 2251036721179. The reversal of 2251036721173 is 3711276301522.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1571307376324 + 679729344849 = 1253518^2 + 824457^2 .

It is a cyclic number.

It is not a de Polignac number, because 2251036721173 - 2³³ = 2242446786581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2251036721179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1125518360586 + 1125518360587.

It is an arithmetic number, because the mean of its divisors is an integer number (1125518360587).

Almost surely, 2^{2251036721173} is an apocalyptic number.

It is an amenable number.

2251036721173 is a deficient number, since it is larger than the sum of its proper divisors (1).

2251036721173 is an equidigital number, since it uses as much as digits as its factorization.

2251036721173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 105840, while the sum is 40.

The spelling of 2251036721173 in words is "two trillion, two hundred fifty-one billion, thirty-six million, seven hundred twenty-one thousand, one hundred seventy-three".