405731 has 2 divisors, whose sum is σ = 405732. Its totient is φ = 405730.

The previous prime is 405719. The next prime is 405749. The reversal of 405731 is 137504.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 405731 - 2⁶ = 405667 is a prime.

It is a super-2 number, since 2×405731² = 329235288722, which contains 22 as substring.

It is a Chen prime.

It is equal to p₃₄₂₈₃ and since 405731 and 34283 have the same sum of digits, it is a Honaker prime.

It is a zygodrome in base 2.

It is not a weakly prime, because it can be changed into another prime (405701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202865 + 202866.

It is an arithmetic number, because the mean of its divisors is an integer number (202866).

2⁴⁰⁵⁷³¹ is an apocalyptic number.

405731 is a deficient number, since it is larger than the sum of its proper divisors (1).

405731 is an equidigital number, since it uses as much as digits as its factorization.

405731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 405731 is about 636.9701719861. The cubic root of 405731 is about 74.0308490809.

The spelling of 405731 in words is "four hundred five thousand, seven hundred thirty-one".