35821 has 4 divisors (see below), whose sum is σ = 36252. Its totient is φ = 35392.

The previous prime is 35809. The next prime is 35831. The reversal of 35821 is 12853.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1225 + 34596 = 35^2 + 186^2 .

It is a cyclic number.

It is not a de Polignac number, because 35821 - 2¹¹ = 33773 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (35801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46 + ... + 271.

It is an arithmetic number, because the mean of its divisors is an integer number (9063).

2³⁵⁸²¹ is an apocalyptic number.

It is an amenable number.

35821 is a deficient number, since it is larger than the sum of its proper divisors (431).

35821 is a wasteful number, since it uses less digits than its factorization.

35821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430.

The product of its digits is 240, while the sum is 19.

The square root of 35821 is about 189.2643653729. The cubic root of 35821 is about 32.9644551468.

The spelling of 35821 in words is "thirty-five thousand, eight hundred twenty-one".