66326531 has 2 divisors, whose sum is σ = 66326532. Its totient is φ = 66326530.

The previous prime is 66326527. The next prime is 66326539. The reversal of 66326531 is 13562366.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66326531 - 2² = 66326527 is a prime.

It is a super-2 number, since 2×66326531² = 8798417428987922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66326539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33163265 + 33163266.

It is an arithmetic number, because the mean of its divisors is an integer number (33163266).

Almost surely, 2^66326531 is an apocalyptic number.

66326531 is a deficient number, since it is larger than the sum of its proper divisors (1).

66326531 is an equidigital number, since it uses as much as digits as its factorization.

66326531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19440, while the sum is 32.

The square root of 66326531 is about 8144.1102030854. The cubic root of 66326531 is about 404.7893656529.

Adding to 66326531 its reverse (13562366), we get a palindrome (79888897).

The spelling of 66326531 in words is "sixty-six million, three hundred twenty-six thousand, five hundred thirty-one".