4821781 has 4 divisors (see below), whose sum is σ = 4912812. Its totient is φ = 4730752.

The previous prime is 4821779. The next prime is 4821793. The reversal of 4821781 is 1871284.

4821781 is nontrivially palindromic in base 12.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1703025 + 3118756 = 1305^2 + 1766^2 .

It is a cyclic number.

It is not a de Polignac number, because 4821781 - 2¹ = 4821779 is a prime.

It is a super-2 number, since 2×4821781² = 46499144023922, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4821721) 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, 45436 + ... + 45541.

It is an arithmetic number, because the mean of its divisors is an integer number (1228203).

Almost surely, 2^4821781 is an apocalyptic number.

It is an amenable number.

4821781 is a deficient number, since it is larger than the sum of its proper divisors (91031).

4821781 is an equidigital number, since it uses as much as digits as its factorization.

4821781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91030.

The product of its digits is 3584, while the sum is 31.

The square root of 4821781 is about 2195.8554141837. The cubic root of 4821781 is about 168.9412981937.

The spelling of 4821781 in words is "four million, eight hundred twenty-one thousand, seven hundred eighty-one".