1373221643 has 2 divisors, whose sum is σ = 1373221644. Its totient is φ = 1373221642.

The previous prime is 1373221639. The next prime is 1373221657. The reversal of 1373221643 is 3461223731.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1373221643 - 2² = 1373221639 is a prime.

It is not a weakly prime, because it can be changed into another prime (1373221243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 686610821 + 686610822.

It is an arithmetic number, because the mean of its divisors is an integer number (686610822).

Almost surely, 2^1373221643 is an apocalyptic number.

1373221643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1373221643 is an equidigital number, since it uses as much as digits as its factorization.

1373221643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 32.

The square root of 1373221643 is about 37057.0053161342. The cubic root of 1373221643 is about 1111.5104408158.

The spelling of 1373221643 in words is "one billion, three hundred seventy-three million, two hundred twenty-one thousand, six hundred forty-three".