3968621 has 4 divisors (see below), whose sum is σ = 4105500. Its totient is φ = 3831744.

The previous prime is 3968617. The next prime is 3968647. The reversal of 3968621 is 1268693.

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 688900 + 3279721 = 830^2 + 1811^2 .

It is a cyclic number.

It is not a de Polignac number, because 3968621 - 2² = 3968617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3968521) 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 3 ways as a sum of consecutive naturals, for example, 68396 + ... + 68453.

It is an arithmetic number, because the mean of its divisors is an integer number (1026375).

Almost surely, 2^3968621 is an apocalyptic number.

It is an amenable number.

3968621 is a deficient number, since it is larger than the sum of its proper divisors (136879).

3968621 is a wasteful number, since it uses less digits than its factorization.

3968621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136878.

The product of its digits is 15552, while the sum is 35.

The square root of 3968621 is about 1992.1398043310. The cubic root of 3968621 is about 158.3239228633.

The spelling of 3968621 in words is "three million, nine hundred sixty-eight thousand, six hundred twenty-one".