440138749 has 2 divisors, whose sum is σ = 440138750. Its totient is φ = 440138748.

The previous prime is 440138747. The next prime is 440138767. The reversal of 440138749 is 947831044.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 437562724 + 2576025 = 20918^2 + 1605^2 .

It is a cyclic number.

It is not a de Polignac number, because 440138749 - 2¹ = 440138747 is a prime.

Together with 440138747, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (440138747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 220069374 + 220069375.

It is an arithmetic number, because the mean of its divisors is an integer number (220069375).

Almost surely, 2^440138749 is an apocalyptic number.

It is an amenable number.

440138749 is a deficient number, since it is larger than the sum of its proper divisors (1).

440138749 is an equidigital number, since it uses as much as digits as its factorization.

440138749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 440138749 is about 20979.4840022342. The cubic root of 440138749 is about 760.6704316064.

The spelling of 440138749 in words is "four hundred forty million, one hundred thirty-eight thousand, seven hundred forty-nine".