66987131 has 8 divisors (see below), whose sum is σ = 69081264. Its totient is φ = 64908000.

The previous prime is 66987121. The next prime is 66987143. The reversal of 66987131 is 13178966.

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

It is a cyclic number.

It is not a de Polignac number, because 66987131 - 2²² = 62792827 is a prime.

It is a super-2 number, since 2×66987131² = 8974551439222322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66987121) 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 7 ways as a sum of consecutive naturals, for example, 5681 + ... + 12893.

It is an arithmetic number, because the mean of its divisors is an integer number (8635158).

Almost surely, 2^66987131 is an apocalyptic number.

66987131 is a deficient number, since it is larger than the sum of its proper divisors (2094133).

66987131 is a wasteful number, since it uses less digits than its factorization.

66987131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7501.

The product of its digits is 54432, while the sum is 41.

The square root of 66987131 is about 8184.5666348317. The cubic root of 66987131 is about 406.1288043683.

The spelling of 66987131 in words is "sixty-six million, nine hundred eighty-seven thousand, one hundred thirty-one".