1312322021 has 8 divisors (see below), whose sum is σ = 1403844120. Its totient is φ = 1222391808.

The previous prime is 1312322003. The next prime is 1312322027. The reversal of 1312322021 is 1202232131.

It can be written as a sum of positive squares in 4 ways, for example, as 338008225 + 974313796 = 18385^2 + 31214^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1312322021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1312322027) 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, 396266 + ... + 399563.

It is an arithmetic number, because the mean of its divisors is an integer number (175480515).

Almost surely, 2^1312322021 is an apocalyptic number.

It is an amenable number.

1312322021 is a deficient number, since it is larger than the sum of its proper divisors (91522099).

1312322021 is an equidigital number, since it uses as much as digits as its factorization.

1312322021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 795943.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 1312322021 is about 36225.9854386323. The cubic root of 1312322021 is about 1094.8302930563.

Adding to 1312322021 its reverse (1202232131), we get a palindrome (2514554152).

The spelling of 1312322021 in words is "one billion, three hundred twelve million, three hundred twenty-two thousand, twenty-one".