500400091 has 4 divisors (see below), whose sum is σ = 500495184. Its totient is φ = 500305000.

The previous prime is 500400079. The next prime is 500400101. The reversal of 500400091 is 190004005.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190004005 = 5 ⋅38000801.

It is a cyclic number.

It is not a de Polignac number, because 500400091 - 2¹⁷ = 500269019 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (500400001) 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, 39160 + ... + 50341.

It is an arithmetic number, because the mean of its divisors is an integer number (125123796).

Almost surely, 2^500400091 is an apocalyptic number.

500400091 is a deficient number, since it is larger than the sum of its proper divisors (95093).

500400091 is an equidigital number, since it uses as much as digits as its factorization.

500400091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95092.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 500400091 is about 22369.6242927770. The cubic root of 500400091 is about 793.9121711673.

Adding to 500400091 its reverse (190004005), we get a palindrome (690404096).

The spelling of 500400091 in words is "five hundred million, four hundred thousand, ninety-one".