440388989 has 2 divisors, whose sum is σ = 440388990. Its totient is φ = 440388988.

The previous prime is 440388979. The next prime is 440388997. The reversal of 440388989 is 989883044.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 427786489 + 12602500 = 20683^2 + 3550^2 .

It is a cyclic number.

It is not a de Polignac number, because 440388989 - 2¹⁶ = 440323453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 440388989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (440388959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 220194494 + 220194495.

It is an arithmetic number, because the mean of its divisors is an integer number (220194495).

Almost surely, 2^440388989 is an apocalyptic number.

It is an amenable number.

440388989 is a deficient number, since it is larger than the sum of its proper divisors (1).

440388989 is an equidigital number, since it uses as much as digits as its factorization.

440388989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1990656, while the sum is 53.

The square root of 440388989 is about 20985.4470764861. The cubic root of 440388989 is about 760.8145635089.

The spelling of 440388989 in words is "four hundred forty million, three hundred eighty-eight thousand, nine hundred eighty-nine".