491121803 has 2 divisors, whose sum is σ = 491121804. Its totient is φ = 491121802.

The previous prime is 491121781. The next prime is 491121833. The reversal of 491121803 is 308121194.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 491121803 - 2²² = 486927499 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (491121833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245560901 + 245560902.

It is an arithmetic number, because the mean of its divisors is an integer number (245560902).

Almost surely, 2^491121803 is an apocalyptic number.

491121803 is a deficient number, since it is larger than the sum of its proper divisors (1).

491121803 is an equidigital number, since it uses as much as digits as its factorization.

491121803 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 491121803 is about 22161.2680819487. The cubic root of 491121803 is about 788.9746902695.

Adding to 491121803 its reverse (308121194), we get a palindrome (799242997).

The spelling of 491121803 in words is "four hundred ninety-one million, one hundred twenty-one thousand, eight hundred three".