5123781 has 12 divisors (see below), whose sum is σ = 7970508. Its totient is φ = 3153024.

The previous prime is 5123777. The next prime is 5123791. The reversal of 5123781 is 1873215.

5123781 is digitally balanced in base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 3006756 + 2117025 = 1734^2 + 1455^2 .

It is not a de Polignac number, because 5123781 - 2² = 5123777 is a prime.

It is a super-2 number, since 2×5123781² = 52506263471922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5123761) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21780 + ... + 22013.

It is an arithmetic number, because the mean of its divisors is an integer number (664209).

Almost surely, 2^5123781 is an apocalyptic number.

It is an amenable number.

5123781 is a deficient number, since it is larger than the sum of its proper divisors (2846727).

5123781 is a wasteful number, since it uses less digits than its factorization.

5123781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43812 (or 43809 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 5123781 is about 2263.5770364624. The cubic root of 5123781 is about 172.3971914171.

Adding to 5123781 its reverse (1873215), we get a palindrome (6996996).

It can be divided in two parts, 51 and 23781, that added together give a palindrome (23832).

The spelling of 5123781 in words is "five million, one hundred twenty-three thousand, seven hundred eighty-one".