405693081 has 6 divisors (see below), whose sum is σ = 586001130. Its totient is φ = 270462048.

The previous prime is 405693037. The next prime is 405693097. The reversal of 405693081 is 180396504.

It can be written as a sum of positive squares in only one way, i.e., 243360000 + 162333081 = 15600^2 + 12741^2 .

It is not a de Polignac number, because 405693081 - 2⁹ = 405692569 is a prime.

It is a super-2 number, since 2×405693081² = 329173751942545122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (405693781) 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 in 5 ways as a sum of consecutive naturals, for example, 22538496 + ... + 22538513.

It is an arithmetic number, because the mean of its divisors is an integer number (97666855).

Almost surely, 2^405693081 is an apocalyptic number.

It is an amenable number.

405693081 is a deficient number, since it is larger than the sum of its proper divisors (180308049).

405693081 is a wasteful number, since it uses less digits than its factorization.

405693081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45077015 (or 45077012 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 405693081 is about 20141.8241726016. The cubic root of 405693081 is about 740.2854273898.

The spelling of 405693081 in words is "four hundred five million, six hundred ninety-three thousand, eighty-one".