4138781 has 4 divisors (see below), whose sum is σ = 4318752. Its totient is φ = 3958812.

The previous prime is 4138777. The next prime is 4138807. The reversal of 4138781 is 1878314.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1878314 = 2 ⋅939157.

It is a cyclic number.

It is not a de Polignac number, because 4138781 - 2² = 4138777 is a prime.

It is a super-2 number, since 2×4138781² = 34259016331922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4138711) 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, 89951 + ... + 89996.

It is an arithmetic number, because the mean of its divisors is an integer number (1079688).

Almost surely, 2^4138781 is an apocalyptic number.

It is an amenable number.

4138781 is a deficient number, since it is larger than the sum of its proper divisors (179971).

4138781 is a wasteful number, since it uses less digits than its factorization.

4138781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179970.

The product of its digits is 5376, while the sum is 32.

The square root of 4138781 is about 2034.3994199763. The cubic root of 4138781 is about 160.5551160818. Note that the first 3 decimals are identical.

The spelling of 4138781 in words is "four million, one hundred thirty-eight thousand, seven hundred eighty-one".