66747531 has 16 divisors (see below), whose sum is σ = 92424960. Its totient is φ = 42796320.

The previous prime is 66747503. The next prime is 66747533. The reversal of 66747531 is 13574766.

It is not a de Polignac number, because 66747531 - 2¹³ = 66739339 is a prime.

It is a super-2 number, since 2×66747531² = 8910465789191922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66747531.

It is not an unprimeable number, because it can be changed into a prime (66747533) 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 15 ways as a sum of consecutive naturals, for example, 23266 + ... + 25976.

It is an arithmetic number, because the mean of its divisors is an integer number (5776560).

Almost surely, 2^66747531 is an apocalyptic number.

66747531 is a deficient number, since it is larger than the sum of its proper divisors (25677429).

66747531 is a wasteful number, since it uses less digits than its factorization.

66747531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3026.

The product of its digits is 105840, while the sum is 39.

The square root of 66747531 is about 8169.9162174407. The cubic root of 66747531 is about 405.6440111998.

The spelling of 66747531 in words is "sixty-six million, seven hundred forty-seven thousand, five hundred thirty-one".