1318683221 has 2 divisors, whose sum is σ = 1318683222. Its totient is φ = 1318683220.

The previous prime is 1318683181. The next prime is 1318683253. The reversal of 1318683221 is 1223868131.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 725224900 + 593458321 = 26930^2 + 24361^2 .

It is a cyclic number.

It is not a de Polignac number, because 1318683221 - 2³⁰ = 244941397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1318683271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 659341610 + 659341611.

It is an arithmetic number, because the mean of its divisors is an integer number (659341611).

Almost surely, 2^1318683221 is an apocalyptic number.

It is an amenable number.

1318683221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1318683221 is an equidigital number, since it uses as much as digits as its factorization.

1318683221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 35.

The square root of 1318683221 is about 36313.6781530046. The cubic root of 1318683221 is about 1096.5964276092.

The spelling of 1318683221 in words is "one billion, three hundred eighteen million, six hundred eighty-three thousand, two hundred twenty-one".