816129 has 16 divisors (see below), whose sum is σ = 1223040. Its totient is φ = 537840.

The previous prime is 816121. The next prime is 816131. The reversal of 816129 is 921618.

It is not a de Polignac number, because 816129 - 2³ = 816121 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (816121) 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 15 ways as a sum of consecutive naturals, for example, 4419 + ... + 4599.

It is an arithmetic number, because the mean of its divisors is an integer number (76440).

It is a Proth number, since it is equal to 797 ⋅ 2¹⁰ + 1 and 797 < 2¹⁰.

2⁸¹⁶¹²⁹ is an apocalyptic number.

It is an amenable number.

816129 is a deficient number, since it is larger than the sum of its proper divisors (406911).

816129 is a wasteful number, since it uses less digits than its factorization.

816129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357 (or 351 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 816129 is about 903.3985831293. The cubic root of 816129 is about 93.4514985757.

The spelling of 816129 in words is "eight hundred sixteen thousand, one hundred twenty-nine".