1408028665 has 4 divisors (see below), whose sum is σ = 1689634404. Its totient is φ = 1126422928.

The previous prime is 1408028663. The next prime is 1408028681. The reversal of 1408028665 is 5668208041.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5668208041 = 19 ⋅298326739.

It can be written as a sum of positive squares in 2 ways, for example, as 167650704 + 1240377961 = 12948^2 + 35219^2 .

It is a cyclic number.

It is not a de Polignac number, because 1408028665 - 2¹ = 1408028663 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1408028663) 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, 140802862 + ... + 140802871.

It is an arithmetic number, because the mean of its divisors is an integer number (422408601).

Almost surely, 2^1408028665 is an apocalyptic number.

It is an amenable number.

1408028665 is a deficient number, since it is larger than the sum of its proper divisors (281605739).

1408028665 is an equidigital number, since it uses as much as digits as its factorization.

1408028665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281605738.

The product of its (nonzero) digits is 92160, while the sum is 40.

The square root of 1408028665 is about 37523.7080390518. The cubic root of 1408028665 is about 1120.8233383145.

The spelling of 1408028665 in words is "one billion, four hundred eight million, twenty-eight thousand, six hundred sixty-five".