312125151721 has 4 divisors (see below), whose sum is σ = 312157596672. Its totient is φ = 312092706772.

The previous prime is 312125151619. The next prime is 312125151749. The reversal of 312125151721 is 127151521213.

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-312125151721 is a prime.

It is a super-2 number, since 2×312125151721² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (312125155721) 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, 16208041 + ... + 16227286.

It is an arithmetic number, because the mean of its divisors is an integer number (78039399168).

Almost surely, 2^312125151721 is an apocalyptic number.

It is an amenable number.

312125151721 is a deficient number, since it is larger than the sum of its proper divisors (32444951).

312125151721 is an equidigital number, since it uses as much as digits as its factorization.

312125151721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32444950.

The product of its digits is 4200, while the sum is 31.

Adding to 312125151721 its reverse (127151521213), we get a palindrome (439276672934).

The spelling of 312125151721 in words is "three hundred twelve billion, one hundred twenty-five million, one hundred fifty-one thousand, seven hundred twenty-one".