391213 has 4 divisors (see below), whose sum is σ = 397120. Its totient is φ = 385308.

The previous prime is 391199. The next prime is 391217. The reversal of 391213 is 312193.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391213 is a prime.

It is a super-2 number, since 2×391213² = 306095222738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2853 + ... + 2986.

It is an arithmetic number, because the mean of its divisors is an integer number (99280).

2³⁹¹²¹³ is an apocalyptic number.

It is an amenable number.

391213 is a deficient number, since it is larger than the sum of its proper divisors (5907).

391213 is an equidigital number, since it uses as much as digits as its factorization.

391213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5906.

The product of its digits is 162, while the sum is 19.

The square root of 391213 is about 625.4702231122. The cubic root of 391213 is about 73.1371039452.

The spelling of 391213 in words is "three hundred ninety-one thousand, two hundred thirteen".