405680081 has 4 divisors (see below), whose sum is σ = 405731172. Its totient is φ = 405628992.

The previous prime is 405680059. The next prime is 405680087. The reversal of 405680081 is 180086504.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 166823056 + 238857025 = 12916^2 + 15455^2 .

It is a cyclic number.

It is not a de Polignac number, because 405680081 - 2¹⁴ = 405663697 is a prime.

It is a super-2 number, since 2×405680081² = 329152656240333122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (405680087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10796 + ... + 30461.

It is an arithmetic number, because the mean of its divisors is an integer number (101432793).

Almost surely, 2^405680081 is an apocalyptic number.

It is an amenable number.

405680081 is a deficient number, since it is larger than the sum of its proper divisors (51091).

405680081 is an equidigital number, since it uses as much as digits as its factorization.

405680081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51090.

The product of its (nonzero) digits is 7680, while the sum is 32.

The square root of 405680081 is about 20141.5014584315. The cubic root of 405680081 is about 740.2775200877.

The spelling of 405680081 in words is "four hundred five million, six hundred eighty thousand, eighty-one".