1321440437 has 2 divisors, whose sum is σ = 1321440438. Its totient is φ = 1321440436.

The previous prime is 1321440431. The next prime is 1321440451. The reversal of 1321440437 is 7340441231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1225420036 + 96020401 = 35006^2 + 9799^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321440437 - 2¹² = 1321436341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321440431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660720218 + 660720219.

It is an arithmetic number, because the mean of its divisors is an integer number (660720219).

Almost surely, 2^1321440437 is an apocalyptic number.

It is an amenable number.

1321440437 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321440437 is an equidigital number, since it uses as much as digits as its factorization.

1321440437 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 29.

The square root of 1321440437 is about 36351.6222058934. The cubic root of 1321440437 is about 1097.3601815092.

Adding to 1321440437 its reverse (7340441231), we get a palindrome (8661881668).

The spelling of 1321440437 in words is "one billion, three hundred twenty-one million, four hundred forty thousand, four hundred thirty-seven".