3216921 has 8 divisors (see below), whose sum is σ = 4315584. Its totient is φ = 2131440.

The previous prime is 3216911. The next prime is 3216931. The reversal of 3216921 is 1296123.

It is an interprime number because it is at equal distance from previous prime (3216911) and next prime (3216931).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3216921 - 2¹³ = 3208729 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 3216891 and 3216900.

It is not an unprimeable number, because it can be changed into a prime (3216911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2710 + ... + 3711.

It is an arithmetic number, because the mean of its divisors is an integer number (539448).

Almost surely, 2^3216921 is an apocalyptic number.

It is an amenable number.

3216921 is a deficient number, since it is larger than the sum of its proper divisors (1098663).

3216921 is a wasteful number, since it uses less digits than its factorization.

3216921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6591.

The product of its digits is 648, while the sum is 24.

The square root of 3216921 is about 1793.5777094957. The cubic root of 3216921 is about 147.6205430385.

The spelling of 3216921 in words is "three million, two hundred sixteen thousand, nine hundred twenty-one".