1343991221 has 2 divisors, whose sum is σ = 1343991222. Its totient is φ = 1343991220.

The previous prime is 1343991217. The next prime is 1343991241. The reversal of 1343991221 is 1221993431.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1318488721 + 25502500 = 36311^2 + 5050^2 .

It is a cyclic number.

It is not a de Polignac number, because 1343991221 - 2² = 1343991217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1343991241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 671995610 + 671995611.

It is an arithmetic number, because the mean of its divisors is an integer number (671995611).

Almost surely, 2^1343991221 is an apocalyptic number.

It is an amenable number.

1343991221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1343991221 is an equidigital number, since it uses as much as digits as its factorization.

1343991221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 35.

The square root of 1343991221 is about 36660.4858260225. The cubic root of 1343991221 is about 1103.5672677104.

The spelling of 1343991221 in words is "one billion, three hundred forty-three million, nine hundred ninety-one thousand, two hundred twenty-one".