665243254431 has 128 divisors (see below), whose sum is σ = 1209212928000. Its totient is φ = 352803589632.

The previous prime is 665243254409. The next prime is 665243254433. The reversal of 665243254431 is 134452342566.

665243254431 is a `hidden beast` number, since 6 + 6 + 524 + 32 + 54 + 43 + 1 = 666.

It is not a de Polignac number, because 665243254431 - 2⁷ = 665243254303 is a prime.

It is a super-2 number, since 2×665243254431² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665243254433) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 334796820 + ... + 334798806.

It is an arithmetic number, because the mean of its divisors is an integer number (9446976000).

Almost surely, 2^665243254431 is an apocalyptic number.

665243254431 is a deficient number, since it is larger than the sum of its proper divisors (543969673569).

665243254431 is a wasteful number, since it uses less digits than its factorization.

665243254431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3418 (or 3412 counting only the distinct ones).

The product of its digits is 2073600, while the sum is 45.

Adding to 665243254431 its reverse (134452342566), we get a palindrome (799695596997).

The spelling of 665243254431 in words is "six hundred sixty-five billion, two hundred forty-three million, two hundred fifty-four thousand, four hundred thirty-one".