402081 has 8 divisors (see below), whose sum is σ = 541824. Its totient is φ = 265200.

The previous prime is 402071. The next prime is 402089. The reversal of 402081 is 180204.

402081 is nontrivially palindromic in base 8.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 402081 - 2⁵ = 402049 is a prime.

It is a super-2 number, since 2×402081² = 323338261122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 402081.

It is not an unprimeable number, because it can be changed into a prime (402089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 361 + ... + 966.

It is an arithmetic number, because the mean of its divisors is an integer number (67728).

2⁴⁰²⁰⁸¹ is an apocalyptic number.

It is an amenable number.

402081 is a deficient number, since it is larger than the sum of its proper divisors (139743).

402081 is a wasteful number, since it uses less digits than its factorization.

402081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1431.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 402081 is about 634.0985727787. The cubic root of 402081 is about 73.8081835212.

Adding to 402081 its reverse (180204), we get a palindrome (582285).

The spelling of 402081 in words is "four hundred two thousand, eighty-one".