4891781 has 2 divisors, whose sum is σ = 4891782. Its totient is φ = 4891780.

The previous prime is 4891763. The next prime is 4891787. The reversal of 4891781 is 1871984.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4879681 + 12100 = 2209^2 + 110^2 .

It is a cyclic number.

It is not a de Polignac number, because 4891781 - 2⁶ = 4891717 is a prime.

It is a super-2 number, since 2×4891781² = 47859042703922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4891787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2445890 + 2445891.

It is an arithmetic number, because the mean of its divisors is an integer number (2445891).

Almost surely, 2^4891781 is an apocalyptic number.

It is an amenable number.

4891781 is a deficient number, since it is larger than the sum of its proper divisors (1).

4891781 is an equidigital number, since it uses as much as digits as its factorization.

4891781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 38.

The square root of 4891781 is about 2211.7371001093. The cubic root of 4891781 is about 169.7549063271.

The spelling of 4891781 in words is "four million, eight hundred ninety-one thousand, seven hundred eighty-one".