66427531 has 2 divisors, whose sum is σ = 66427532. Its totient is φ = 66427530.

The previous prime is 66427523. The next prime is 66427547. The reversal of 66427531 is 13572466.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66427531 - 2³ = 66427523 is a prime.

It is a super-2 number, since 2×66427531² = 8825233749511922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66427631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33213765 + 33213766.

It is an arithmetic number, because the mean of its divisors is an integer number (33213766).

Almost surely, 2^66427531 is an apocalyptic number.

66427531 is a deficient number, since it is larger than the sum of its proper divisors (1).

66427531 is an equidigital number, since it uses as much as digits as its factorization.

66427531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 34.

The square root of 66427531 is about 8150.3086444625. The cubic root of 66427531 is about 404.9947283772.

Adding to 66427531 its reverse (13572466), we get a palindrome (79999997).

The spelling of 66427531 in words is "sixty-six million, four hundred twenty-seven thousand, five hundred thirty-one".