291406 has 4 divisors (see below), whose sum is σ = 437112. Its totient is φ = 145702.

The previous prime is 291377. The next prime is 291419. The reversal of 291406 is 604192.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a nialpdrome in base 5.

It is a zygodrome in base 5.

It is a congruent number.

It is an unprimeable number.

291406 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72850 + ... + 72853.

It is an arithmetic number, because the mean of its divisors is an integer number (109278).

2²⁹¹⁴⁰⁶ is an apocalyptic number.

291406 is a deficient number, since it is larger than the sum of its proper divisors (145706).

291406 is a wasteful number, since it uses less digits than its factorization.

291406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145705.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 291406 is about 539.8203404838. The cubic root of 291406 is about 66.2978579083.

Adding to 291406 its reverse (604192), we get a palindrome (895598).

The spelling of 291406 in words is "two hundred ninety-one thousand, four hundred six".