66425632381 has 2 divisors, whose sum is σ = 66425632382. Its totient is φ = 66425632380.

The previous prime is 66425632349. The next prime is 66425632411. The reversal of 66425632381 is 18323652466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45663416100 + 20762216281 = 213690^2 + 144091^2 .

It is a cyclic number.

It is not a de Polignac number, because 66425632381 - 2⁵ = 66425632349 is a prime.

It is a super-3 number, since 3×66425632381³ (a number of 33 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66425632681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33212816190 + 33212816191.

It is an arithmetic number, because the mean of its divisors is an integer number (33212816191).

Almost surely, 2^66425632381 is an apocalyptic number.

It is an amenable number.

66425632381 is a deficient number, since it is larger than the sum of its proper divisors (1).

66425632381 is an equidigital number, since it uses as much as digits as its factorization.

66425632381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1244160, while the sum is 46.

The spelling of 66425632381 in words is "sixty-six billion, four hundred twenty-five million, six hundred thirty-two thousand, three hundred eighty-one".