1638436241 has 12 divisors (see below), whose sum is σ = 1791749340. Its totient is φ = 1497412800.

The previous prime is 1638436237. The next prime is 1638436243. The reversal of 1638436241 is 1426348361.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 178890625 + 1459545616 = 13375^2 + 38204^2 .

It is not a de Polignac number, because 1638436241 - 2² = 1638436237 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1638436195 and 1638436204.

It is not an unprimeable number, because it can be changed into a prime (1638436243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30926 + ... + 65063.

It is an arithmetic number, because the mean of its divisors is an integer number (149312445).

Almost surely, 2^1638436241 is an apocalyptic number.

It is an amenable number.

1638436241 is a deficient number, since it is larger than the sum of its proper divisors (153313099).

1638436241 is a wasteful number, since it uses less digits than its factorization.

1638436241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96116 (or 96103 counting only the distinct ones).

The product of its digits is 82944, while the sum is 38.

The square root of 1638436241 is about 40477.6017199636. The cubic root of 1638436241 is about 1178.8987717525.

It can be divided in two parts, 16384 and 36241, that added together give a palindrome (52625).

The spelling of 1638436241 in words is "one billion, six hundred thirty-eight million, four hundred thirty-six thousand, two hundred forty-one".