1220209993 has 2 divisors, whose sum is σ = 1220209994. Its totient is φ = 1220209992.

The previous prime is 1220209973. The next prime is 1220209999. The reversal of 1220209993 is 3999020221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 728568064 + 491641929 = 26992^2 + 22173^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1220209993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1220209999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610104996 + 610104997.

It is an arithmetic number, because the mean of its divisors is an integer number (610104997).

Almost surely, 2^1220209993 is an apocalyptic number.

It is an amenable number.

1220209993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220209993 is an equidigital number, since it uses as much as digits as its factorization.

1220209993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 1220209993 is about 34931.5043048535. The cubic root of 1220209993 is about 1068.5910336710.

The spelling of 1220209993 in words is "one billion, two hundred twenty million, two hundred nine thousand, nine hundred ninety-three".