66989331 has 6 divisors (see below), whose sum is σ = 96762380. Its totient is φ = 44659548.

The previous prime is 66989309. The next prime is 66989353. The reversal of 66989331 is 13398966.

It is an interprime number because it is at equal distance from previous prime (66989309) and next prime (66989353).

It is not a de Polignac number, because 66989331 - 2⁹ = 66988819 is a prime.

It is a super-2 number, since 2×66989331² = 8975140935655122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66989371) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3721621 + ... + 3721638.

Almost surely, 2^66989331 is an apocalyptic number.

66989331 is a deficient number, since it is larger than the sum of its proper divisors (29773049).

66989331 is a wasteful number, since it uses less digits than its factorization.

66989331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7443265 (or 7443262 counting only the distinct ones).

The product of its digits is 209952, while the sum is 45.

The square root of 66989331 is about 8184.7010330250. The cubic root of 66989331 is about 406.1332503645.

It can be divided in two parts, 669 and 89331, that added together give a square (90000 = 300²).

The spelling of 66989331 in words is "sixty-six million, nine hundred eighty-nine thousand, three hundred thirty-one".