4036638421 has 4 divisors (see below), whose sum is σ = 4036791244. Its totient is φ = 4036485600.

The previous prime is 4036638409. The next prime is 4036638467. The reversal of 4036638421 is 1248366304.

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 350812900 + 3685825521 = 18730^2 + 60711^2 .

It is a cyclic number.

It is not a de Polignac number, because 4036638421 - 2¹⁵ = 4036605653 is a prime.

It is a deceptive number, since it divides R_4036638420.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4036638481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25470 + ... + 93391.

It is an arithmetic number, because the mean of its divisors is an integer number (1009197811).

Almost surely, 2^4036638421 is an apocalyptic number.

4036638421 is the 33961-st nonagonal number.

It is an amenable number.

4036638421 is a deficient number, since it is larger than the sum of its proper divisors (152823).

4036638421 is a wasteful number, since it uses less digits than its factorization.

4036638421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152822.

The product of its (nonzero) digits is 82944, while the sum is 37.

The square root of 4036638421 is about 63534.5450994969. The cubic root of 4036638421 is about 1592.2329846649.

It can be divided in two parts, 40366 and 38421, that added together give a palindrome (78787).

The spelling of 4036638421 in words is "four billion, thirty-six million, six hundred thirty-eight thousand, four hundred twenty-one".