423332551981 has 2 divisors, whose sum is σ = 423332551982. Its totient is φ = 423332551980.

The previous prime is 423332551979. The next prime is 423332552009. The reversal of 423332551981 is 189155233324.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 253880945956 + 169451606025 = 503866^2 + 411645^2 .

It is a cyclic number.

It is not a de Polignac number, because 423332551981 - 2¹ = 423332551979 is a prime.

It is a super-2 number, since 2×423332551981² (a number of 24 digits) contains 22 as substring.

Together with 423332551979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (423332551781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 211666275990 + 211666275991.

It is an arithmetic number, because the mean of its divisors is an integer number (211666275991).

Almost surely, 2^423332551981 is an apocalyptic number.

It is an amenable number.

423332551981 is a deficient number, since it is larger than the sum of its proper divisors (1).

423332551981 is an equidigital number, since it uses as much as digits as its factorization.

423332551981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 777600, while the sum is 46.

The spelling of 423332551981 in words is "four hundred twenty-three billion, three hundred thirty-two million, five hundred fifty-one thousand, nine hundred eighty-one".