3213991 has 4 divisors (see below), whose sum is σ = 3506184. Its totient is φ = 2921800.

The previous prime is 3213979. The next prime is 3214007. The reversal of 3213991 is 1993123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1993123 = 11 ⋅181193.

It is a cyclic number.

It is not a de Polignac number, because 3213991 - 2⁹ = 3213479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3213961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 146080 + ... + 146101.

It is an arithmetic number, because the mean of its divisors is an integer number (876546).

Almost surely, 2^3213991 is an apocalyptic number.

3213991 is a deficient number, since it is larger than the sum of its proper divisors (292193).

3213991 is a wasteful number, since it uses less digits than its factorization.

3213991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292192.

The product of its digits is 1458, while the sum is 28.

The square root of 3213991 is about 1792.7607202301. The cubic root of 3213991 is about 147.5757113942.

The spelling of 3213991 in words is "three million, two hundred thirteen thousand, nine hundred ninety-one".