1312203421 has 4 divisors (see below), whose sum is σ = 1313441244. Its totient is φ = 1310965600.

The previous prime is 1312203419. The next prime is 1312203467. The reversal of 1312203421 is 1243022131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1243022131 = 13 ⋅95617087.

It can be written as a sum of positive squares in 2 ways, for example, as 973128025 + 339075396 = 31195^2 + 18414^2 .

It is a cyclic number.

It is not a de Polignac number, because 1312203421 - 2¹ = 1312203419 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 (1312203721) 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, 617320 + ... + 619441.

It is an arithmetic number, because the mean of its divisors is an integer number (328360311).

Almost surely, 2^1312203421 is an apocalyptic number.

It is an amenable number.

1312203421 is a deficient number, since it is larger than the sum of its proper divisors (1237823).

1312203421 is a wasteful number, since it uses less digits than its factorization.

1312203421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237822.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 1312203421 is about 36224.3484551482. The cubic root of 1312203421 is about 1094.7973106067.

Adding to 1312203421 its reverse (1243022131), we get a palindrome (2555225552).

The spelling of 1312203421 in words is "one billion, three hundred twelve million, two hundred three thousand, four hundred twenty-one".