819801 has 20 divisors (see below), whose sum is σ = 1270500. Its totient is φ = 526176.

The previous prime is 819799. The next prime is 819811. The reversal of 819801 is 108918.

It can be written as a sum of positive squares in 2 ways, for example, as 518400 + 301401 = 720^2 + 549^2 .

It is not a de Polignac number, because 819801 - 2¹ = 819799 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (819811) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2175 + ... + 2523.

It is an arithmetic number, because the mean of its divisors is an integer number (63525).

2⁸¹⁹⁸⁰¹ is an apocalyptic number.

819801 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

819801 is a deficient number, since it is larger than the sum of its proper divisors (450699).

819801 is a wasteful number, since it uses less digits than its factorization.

819801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390 (or 381 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 819801 is about 905.4286277780. The cubic root of 819801 is about 93.5914439911.

It can be divided in two parts, 81 and 9801, that multiplied together give a square (793881 = 891²).

The spelling of 819801 in words is "eight hundred nineteen thousand, eight hundred one".