1438285661 has 4 divisors (see below), whose sum is σ = 1438465500. Its totient is φ = 1438105824.

The previous prime is 1438285649. The next prime is 1438285679. The reversal of 1438285661 is 1665828341.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1168340761 + 269944900 = 34181^2 + 16430^2 .

It is a cyclic number.

It is not a de Polignac number, because 1438285661 - 2¹⁰ = 1438284637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1438285621) 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, 77336 + ... + 94113.

It is an arithmetic number, because the mean of its divisors is an integer number (359616375).

Almost surely, 2^1438285661 is an apocalyptic number.

It is an amenable number.

1438285661 is a deficient number, since it is larger than the sum of its proper divisors (179839).

1438285661 is an equidigital number, since it uses as much as digits as its factorization.

1438285661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179838.

The product of its digits is 276480, while the sum is 44.

The square root of 1438285661 is about 37924.7367953952. The cubic root of 1438285661 is about 1128.7949303826.

The spelling of 1438285661 in words is "one billion, four hundred thirty-eight million, two hundred eighty-five thousand, six hundred sixty-one".