2172824261 has 2 divisors, whose sum is σ = 2172824262. Its totient is φ = 2172824260.

The previous prime is 2172824219. The next prime is 2172824267. The reversal of 2172824261 is 1624282712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1722748036 + 450076225 = 41506^2 + 21215^2 .

It is a cyclic number.

It is not a de Polignac number, because 2172824261 - 2¹⁴ = 2172807877 is a prime.

It is a super-2 number, since 2×2172824261² = 9442330538380392242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2172824267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1086412130 + 1086412131.

It is an arithmetic number, because the mean of its divisors is an integer number (1086412131).

Almost surely, 2^2172824261 is an apocalyptic number.

It is an amenable number.

2172824261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2172824261 is an equidigital number, since it uses as much as digits as its factorization.

2172824261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21504, while the sum is 35.

The square root of 2172824261 is about 46613.5630584061. The cubic root of 2172824261 is about 1295.2140115291.

The spelling of 2172824261 in words is "two billion, one hundred seventy-two million, eight hundred twenty-four thousand, two hundred sixty-one".