66716531 has 8 divisors (see below), whose sum is σ = 76312320. Its totient is φ = 57136968.

The previous prime is 66716519. The next prime is 66716539. The reversal of 66716531 is 13561766.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66716531 - 2¹⁰ = 66715507 is a prime.

It is a super-2 number, since 2×66716531² = 8902191017347922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66716491 and 66716500.

It is not an unprimeable number, because it can be changed into a prime (66716539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6650 + ... + 13328.

It is an arithmetic number, because the mean of its divisors is an integer number (9539040).

Almost surely, 2^66716531 is an apocalyptic number.

66716531 is a deficient number, since it is larger than the sum of its proper divisors (9595789).

66716531 is a wasteful number, since it uses less digits than its factorization.

66716531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8113.

The product of its digits is 22680, while the sum is 35.

The square root of 66716531 is about 8168.0187928285. The cubic root of 66716531 is about 405.5812028261.

The spelling of 66716531 in words is "sixty-six million, seven hundred sixteen thousand, five hundred thirty-one".