340561 has 16 divisors (see below), whose sum is σ = 411264. Its totient is φ = 278784.

The previous prime is 340559. The next prime is 340573. The reversal of 340561 is 165043.

It is a 2-Lehmer number, since φ(340561) divides (340561-1)².

It is a cyclic number.

It is a Carmichael number.

It is not a de Polignac number, because 340561 - 2¹ = 340559 is a prime.

It is a deceptive number, since it divides R₃₄₀₅₆₀.

340561 is a modest number, since divided by 561 gives 34 as remainder.

340561 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (340541) 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, 5050 + ... + 5116.

It is an arithmetic number, because the mean of its divisors is an integer number (25704).

It is a Poulet number, since it divides 2³⁴⁰⁵⁶⁰-1.

2³⁴⁰⁵⁶¹ is an apocalyptic number.

It is an amenable number.

340561 is a deficient number, since it is larger than the sum of its proper divisors (70703).

340561 is a wasteful number, since it uses less digits than its factorization.

340561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 340561 is about 583.5760447448. The cubic root of 340561 is about 69.8336868016.

The spelling of 340561 in words is "three hundred forty thousand, five hundred sixty-one".