1550220643 has 2 divisors, whose sum is σ = 1550220644. Its totient is φ = 1550220642.

The previous prime is 1550220629. The next prime is 1550220647. The reversal of 1550220643 is 3460220551.

It is a strong prime.

It is an emirp because it is prime and its reverse (3460220551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1550220643 - 2⁵ = 1550220611 is a prime.

It is not a weakly prime, because it can be changed into another prime (1550220647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775110321 + 775110322.

It is an arithmetic number, because the mean of its divisors is an integer number (775110322).

Almost surely, 2^1550220643 is an apocalyptic number.

1550220643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1550220643 is an equidigital number, since it uses as much as digits as its factorization.

1550220643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 1550220643 is about 39372.8414392459. The cubic root of 1550220643 is about 1157.3494384072.

The spelling of 1550220643 in words is "one billion, five hundred fifty million, two hundred twenty thousand, six hundred forty-three".