405670261 has 2 divisors, whose sum is σ = 405670262. Its totient is φ = 405670260.

The previous prime is 405670211. The next prime is 405670351. The reversal of 405670261 is 162076504.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 380016036 + 25654225 = 19494^2 + 5065^2 .

It is a cyclic number.

It is not a de Polignac number, because 405670261 - 2¹¹ = 405668213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405670211) 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, 202835130 + 202835131.

It is an arithmetic number, because the mean of its divisors is an integer number (202835131).

Almost surely, 2^405670261 is an apocalyptic number.

It is an amenable number.

405670261 is a deficient number, since it is larger than the sum of its proper divisors (1).

405670261 is an equidigital number, since it uses as much as digits as its factorization.

405670261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 405670261 is about 20141.2576816841. The cubic root of 405670261 is about 740.2715469212.

The spelling of 405670261 in words is "four hundred five million, six hundred seventy thousand, two hundred sixty-one".