312649 has 4 divisors (see below), whose sum is σ = 323460. Its totient is φ = 301840.

The previous prime is 312643. The next prime is 312673. The reversal of 312649 is 946213.

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 126025 + 186624 = 355^2 + 432^2 .

It is a cyclic number.

It is not a de Polignac number, because 312649 - 2⁵ = 312617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (312643) 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, 5362 + ... + 5419.

It is an arithmetic number, because the mean of its divisors is an integer number (80865).

2³¹²⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

312649 is a deficient number, since it is larger than the sum of its proper divisors (10811).

312649 is a wasteful number, since it uses less digits than its factorization.

312649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10810.

The product of its digits is 1296, while the sum is 25.

The square root of 312649 is about 559.1502481444. The cubic root of 312649 is about 67.8712239872.

It can be divided in two parts, 312 and 649, that added together give a square (961 = 31²).

The spelling of 312649 in words is "three hundred twelve thousand, six hundred forty-nine".