400291 has 2 divisors, whose sum is σ = 400292. Its totient is φ = 400290.

The previous prime is 400277. The next prime is 400297. The reversal of 400291 is 192004.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 400291 - 2¹³ = 392099 is a prime.

400291 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (400297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200145 + 200146.

It is an arithmetic number, because the mean of its divisors is an integer number (200146).

2⁴⁰⁰²⁹¹ is an apocalyptic number.

400291 is a deficient number, since it is larger than the sum of its proper divisors (1).

400291 is an equidigital number, since it uses as much as digits as its factorization.

400291 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 400291 is about 632.6855459073. The cubic root of 400291 is about 73.6984931944.

Adding to 400291 its reverse (192004), we get a palindrome (592295).

The spelling of 400291 in words is "four hundred thousand, two hundred ninety-one".