505457891 has 2 divisors, whose sum is σ = 505457892. Its totient is φ = 505457890.

The previous prime is 505457861. The next prime is 505457899. The reversal of 505457891 is 198754505.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 505457891 - 2¹⁴ = 505441507 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (505457899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252728945 + 252728946.

It is an arithmetic number, because the mean of its divisors is an integer number (252728946).

Almost surely, 2^505457891 is an apocalyptic number.

505457891 is a deficient number, since it is larger than the sum of its proper divisors (1).

505457891 is an equidigital number, since it uses as much as digits as its factorization.

505457891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252000, while the sum is 44.

The square root of 505457891 is about 22482.3906869354. The cubic root of 505457891 is about 796.5780351282.

The spelling of 505457891 in words is "five hundred five million, four hundred fifty-seven thousand, eight hundred ninety-one".