312051661 has 4 divisors (see below), whose sum is σ = 317167324. Its totient is φ = 306936000.

The previous prime is 312051637. The next prime is 312051667. The reversal of 312051661 is 166150213.

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 151142436 + 160909225 = 12294^2 + 12685^2 .

It is a cyclic number.

It is not a de Polignac number, because 312051661 - 2¹⁷ = 311920589 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 (312051667) 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, 2557740 + ... + 2557861.

It is an arithmetic number, because the mean of its divisors is an integer number (79291831).

Almost surely, 2^312051661 is an apocalyptic number.

It is an amenable number.

312051661 is a deficient number, since it is larger than the sum of its proper divisors (5115663).

312051661 is an equidigital number, since it uses as much as digits as its factorization.

312051661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5115662.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 312051661 is about 17664.9840362226. The cubic root of 312051661 is about 678.2797210186.

The spelling of 312051661 in words is "three hundred twelve million, fifty-one thousand, six hundred sixty-one".