1649172169 has 2 divisors, whose sum is σ = 1649172170. Its totient is φ = 1649172168.

The previous prime is 1649172097. The next prime is 1649172199. The reversal of 1649172169 is 9612719461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1640250000 + 8922169 = 40500^2 + 2987^2 .

It is an emirp because it is prime and its reverse (9612719461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1649172169 - 2¹¹ = 1649170121 is a prime.

It is a super-2 number, since 2×1649172169² = 5439537686008329122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1649172199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 824586084 + 824586085.

It is an arithmetic number, because the mean of its divisors is an integer number (824586085).

Almost surely, 2^1649172169 is an apocalyptic number.

It is an amenable number.

1649172169 is a deficient number, since it is larger than the sum of its proper divisors (1).

1649172169 is an equidigital number, since it uses as much as digits as its factorization.

1649172169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 46.

The square root of 1649172169 is about 40610.0008495444. Note that the first 3 decimals coincide. The cubic root of 1649172169 is about 1181.4680972995.

The spelling of 1649172169 in words is "one billion, six hundred forty-nine million, one hundred seventy-two thousand, one hundred sixty-nine".