423131993 has 2 divisors, whose sum is σ = 423131994. Its totient is φ = 423131992.

The previous prime is 423131971. The next prime is 423132043. The reversal of 423131993 is 399131324.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 258984649 + 164147344 = 16093^2 + 12812^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-423131993 is a prime.

It is not a weakly prime, because it can be changed into another prime (423131923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 211565996 + 211565997.

It is an arithmetic number, because the mean of its divisors is an integer number (211565997).

Almost surely, 2^423131993 is an apocalyptic number.

It is an amenable number.

423131993 is a deficient number, since it is larger than the sum of its proper divisors (1).

423131993 is an equidigital number, since it uses as much as digits as its factorization.

423131993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17496, while the sum is 35.

The square root of 423131993 is about 20570.1724105560. The cubic root of 423131993 is about 750.7441461585.

The spelling of 423131993 in words is "four hundred twenty-three million, one hundred thirty-one thousand, nine hundred ninety-three".