366821 has 16 divisors (see below), whose sum is σ = 470400. Its totient is φ = 278208.

The previous prime is 366811. The next prime is 366829. The reversal of 366821 is 128663.

It is not a de Polignac number, because 366821 - 2¹⁰ = 365797 is a prime.

It is an Ulam number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 366821.

It is not an unprimeable number, because it can be changed into a prime (366829) 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, 2570 + ... + 2708.

It is an arithmetic number, because the mean of its divisors is an integer number (29400).

2³⁶⁶⁸²¹ is an apocalyptic number.

It is an amenable number.

366821 is a deficient number, since it is larger than the sum of its proper divisors (103579).

366821 is a wasteful number, since it uses less digits than its factorization.

366821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188.

The product of its digits is 1728, while the sum is 26.

The square root of 366821 is about 605.6574939683. The cubic root of 366821 is about 71.5843463173.

It can be divided in two parts, 3668 and 21, that multiplied together give a triangular number (77028 = T₃₉₂).

The spelling of 366821 in words is "three hundred sixty-six thousand, eight hundred twenty-one".