3911921 has 16 divisors (see below), whose sum is σ = 4612608. Its totient is φ = 3283200.

The previous prime is 3911911. The next prime is 3911923. The reversal of 3911921 is 1291193.

It is a cyclic number.

It is not a de Polignac number, because 3911921 - 2¹⁸ = 3649777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3911923) 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 15 ways as a sum of consecutive naturals, for example, 6566 + ... + 7136.

It is an arithmetic number, because the mean of its divisors is an integer number (288288).

Almost surely, 2^3911921 is an apocalyptic number.

3911921 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

3911921 is a deficient number, since it is larger than the sum of its proper divisors (700687).

3911921 is a wasteful number, since it uses less digits than its factorization.

3911921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 632.

The product of its digits is 486, while the sum is 26.

The square root of 3911921 is about 1977.8576794097. The cubic root of 3911921 is about 157.5663078492.

It can be divided in two parts, 391192 and 1, that added together give a palindrome (391193).

The spelling of 3911921 in words is "three million, nine hundred eleven thousand, nine hundred twenty-one".