340021 has 4 divisors (see below), whose sum is σ = 370944. Its totient is φ = 309100.

The previous prime is 340007. The next prime is 340027. The reversal of 340021 is 120043.

340021 is nontrivially palindromic in base 16.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 340021 - 2¹¹ = 337973 is a prime.

It is a super-2 number, since 2×340021² = 231228560882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (340027) 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, 15445 + ... + 15466.

It is an arithmetic number, because the mean of its divisors is an integer number (92736).

2³⁴⁰⁰²¹ is an apocalyptic number.

It is an amenable number.

340021 is a deficient number, since it is larger than the sum of its proper divisors (30923).

340021 is a wasteful number, since it uses less digits than its factorization.

340021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30922.

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 340021 is about 583.1131965579. The cubic root of 340021 is about 69.7967574020.

Adding to 340021 its reverse (120043), we get a palindrome (460064).

The spelling of 340021 in words is "three hundred forty thousand, twenty-one", and thus it is an iban number.