66735531 has 12 divisors (see below), whose sum is σ = 99001552. Its totient is φ = 43287696.

The previous prime is 66735521. The next prime is 66735541. The reversal of 66735531 is 13553766.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66735521) and next prime (66735541).

It is not a de Polignac number, because 66735531 - 2¹⁸ = 66473387 is a prime.

It is a super-2 number, since 2×66735531² = 8907262195703922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66735511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 99871 + ... + 100536.

Almost surely, 2^66735531 is an apocalyptic number.

66735531 is a deficient number, since it is larger than the sum of its proper divisors (32266021).

66735531 is a wasteful number, since it uses less digits than its factorization.

66735531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200450 (or 200447 counting only the distinct ones).

The product of its digits is 56700, while the sum is 36.

The square root of 66735531 is about 8169.1817827736. The cubic root of 66735531 is about 405.6197005883.

The spelling of 66735531 in words is "sixty-six million, seven hundred thirty-five thousand, five hundred thirty-one".