405992261 has 2 divisors, whose sum is σ = 405992262. Its totient is φ = 405992260.

The previous prime is 405992233. The next prime is 405992263. The reversal of 405992261 is 162299504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 290020900 + 115971361 = 17030^2 + 10769^2 .

It is a cyclic number.

It is not a de Polignac number, because 405992261 - 2²⁶ = 338883397 is a prime.

Together with 405992263, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405992263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202996130 + 202996131.

It is an arithmetic number, because the mean of its divisors is an integer number (202996131).

Almost surely, 2^405992261 is an apocalyptic number.

It is an amenable number.

405992261 is a deficient number, since it is larger than the sum of its proper divisors (1).

405992261 is an equidigital number, since it uses as much as digits as its factorization.

405992261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 405992261 is about 20149.2496386342. The cubic root of 405992261 is about 740.4673581674.

The spelling of 405992261 in words is "four hundred five million, nine hundred ninety-two thousand, two hundred sixty-one".