491373893 has 2 divisors, whose sum is σ = 491373894. Its totient is φ = 491373892.

The previous prime is 491373847. The next prime is 491373923. The reversal of 491373893 is 398373194.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 412821124 + 78552769 = 20318^2 + 8863^2 .

It is a cyclic number.

It is not a de Polignac number, because 491373893 - 2²⁶ = 424265029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (490373893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245686946 + 245686947.

It is an arithmetic number, because the mean of its divisors is an integer number (245686947).

Almost surely, 2^491373893 is an apocalyptic number.

It is an amenable number.

491373893 is a deficient number, since it is larger than the sum of its proper divisors (1).

491373893 is an equidigital number, since it uses as much as digits as its factorization.

491373893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 489888, while the sum is 47.

The square root of 491373893 is about 22166.9549780749. The cubic root of 491373893 is about 789.1096592378.

The spelling of 491373893 in words is "four hundred ninety-one million, three hundred seventy-three thousand, eight hundred ninety-three".