1955639993 has 2 divisors, whose sum is σ = 1955639994. Its totient is φ = 1955639992.

The previous prime is 1955639981. The next prime is 1955640007. The reversal of 1955639993 is 3999365591.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1784893504 + 170746489 = 42248^2 + 13067^2 .

It is a cyclic number.

It is not a de Polignac number, because 1955639993 - 2¹⁸ = 1955377849 is a prime.

It is not a weakly prime, because it can be changed into another prime (1955639293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 977819996 + 977819997.

It is an arithmetic number, because the mean of its divisors is an integer number (977819997).

Almost surely, 2^1955639993 is an apocalyptic number.

It is an amenable number.

1955639993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1955639993 is an equidigital number, since it uses as much as digits as its factorization.

1955639993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8857350, while the sum is 59.

The square root of 1955639993 is about 44222.6185678777. The cubic root of 1955639993 is about 1250.5363017115.

The spelling of 1955639993 in words is "one billion, nine hundred fifty-five million, six hundred thirty-nine thousand, nine hundred ninety-three".