66737774431 has 2 divisors, whose sum is σ = 66737774432. Its totient is φ = 66737774430.

The previous prime is 66737774399. The next prime is 66737774479. The reversal of 66737774431 is 13447773766.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66737774431 - 2⁵ = 66737774399 is a prime.

It is a super-2 number, since 2×66737774431² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66737714431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33368887215 + 33368887216.

It is an arithmetic number, because the mean of its divisors is an integer number (33368887216).

Almost surely, 2^66737774431 is an apocalyptic number.

66737774431 is a deficient number, since it is larger than the sum of its proper divisors (1).

66737774431 is an equidigital number, since it uses as much as digits as its factorization.

66737774431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12446784, while the sum is 55.

The spelling of 66737774431 in words is "sixty-six billion, seven hundred thirty-seven million, seven hundred seventy-four thousand, four hundred thirty-one".