312405661 has 8 divisors (see below), whose sum is σ = 323403480. Its totient is φ = 301422912.

The previous prime is 312405659. The next prime is 312405671. The reversal of 312405661 is 166504213.

It can be written as a sum of positive squares in 4 ways, for example, as 13461561 + 298944100 = 3669^2 + 17290^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 312405661 - 2¹ = 312405659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (312405641) 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, 53271 + ... + 58843.

It is an arithmetic number, because the mean of its divisors is an integer number (40425435).

Almost surely, 2^312405661 is an apocalyptic number.

It is an amenable number.

312405661 is a deficient number, since it is larger than the sum of its proper divisors (10997819).

312405661 is a wasteful number, since it uses less digits than its factorization.

312405661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7535.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 312405661 is about 17675.0010183875. The cubic root of 312405661 is about 678.5361104911.

Adding to 312405661 its reverse (166504213), we get a palindrome (478909874).

The spelling of 312405661 in words is "three hundred twelve million, four hundred five thousand, six hundred sixty-one".