2820172681 has 2 divisors, whose sum is σ = 2820172682. Its totient is φ = 2820172680.

The previous prime is 2820172633. The next prime is 2820172697. The reversal of 2820172681 is 1862710282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2677131081 + 143041600 = 51741^2 + 11960^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2820172681 is a prime.

It is a super-2 number, since 2×2820172681² = 15906747901317455522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2820172681.

It is not a weakly prime, because it can be changed into another prime (2820172181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1410086340 + 1410086341.

It is an arithmetic number, because the mean of its divisors is an integer number (1410086341).

Almost surely, 2^2820172681 is an apocalyptic number.

It is an amenable number.

2820172681 is a deficient number, since it is larger than the sum of its proper divisors (1).

2820172681 is an equidigital number, since it uses as much as digits as its factorization.

2820172681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 2820172681 is about 53105.2980501946. The cubic root of 2820172681 is about 1412.8364812603.

The spelling of 2820172681 in words is "two billion, eight hundred twenty million, one hundred seventy-two thousand, six hundred eighty-one".