816405 has 16 divisors (see below), whose sum is σ = 1342464. Its totient is φ = 423360.

The previous prime is 816401. The next prime is 816427. The reversal of 816405 is 504618.

816405 = T₁₁₀ + T₁₁₁ + ... + T₁₈₃.

816405 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 816405 - 2² = 816401 is a prime.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 181 + ... + 1290.

It is an arithmetic number, because the mean of its divisors is an integer number (83904).

2⁸¹⁶⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

816405 is a deficient number, since it is larger than the sum of its proper divisors (526059).

816405 is a wasteful number, since it uses less digits than its factorization.

816405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1516.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 816405 is about 903.5513267103. The cubic root of 816405 is about 93.4620319213.

It can be divided in two parts, 816 and 405, that added together give a palindrome (1221).

The spelling of 816405 in words is "eight hundred sixteen thousand, four hundred five".