423855517681 has 2 divisors, whose sum is σ = 423855517682. Its totient is φ = 423855517680.

The previous prime is 423855517663. The next prime is 423855517699. The reversal of 423855517681 is 186715558324.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (423855517663) and next prime (423855517699).

It can be written as a sum of positive squares in only one way, i.e., 379751737600 + 44103780081 = 616240^2 + 210009^2 .

It is a cyclic number.

It is not a de Polignac number, because 423855517681 - 2²⁵ = 423821963249 is a prime.

It is a super-2 number, since 2×423855517681² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (423855512681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 211927758840 + 211927758841.

It is an arithmetic number, because the mean of its divisors is an integer number (211927758841).

Almost surely, 2^423855517681 is an apocalyptic number.

It is an amenable number.

423855517681 is a deficient number, since it is larger than the sum of its proper divisors (1).

423855517681 is an equidigital number, since it uses as much as digits as its factorization.

423855517681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064000, while the sum is 55.

The spelling of 423855517681 in words is "four hundred twenty-three billion, eight hundred fifty-five million, five hundred seventeen thousand, six hundred eighty-one".