66345031 has 4 divisors (see below), whose sum is σ = 66374392. Its totient is φ = 66315672.

The previous prime is 66344989. The next prime is 66345043. The reversal of 66345031 is 13054366.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66345031 is a prime.

It is a super-2 number, since 2×66345031² = 8803326276781922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66345091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10980 + ... + 15913.

It is an arithmetic number, because the mean of its divisors is an integer number (16593598).

Almost surely, 2^66345031 is an apocalyptic number.

66345031 is a deficient number, since it is larger than the sum of its proper divisors (29361).

66345031 is a wasteful number, since it uses less digits than its factorization.

66345031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29360.

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 66345031 is about 8145.2459140286. The cubic root of 66345031 is about 404.8269971859.

Adding to 66345031 its reverse (13054366), we get a palindrome (79399397).

The spelling of 66345031 in words is "sixty-six million, three hundred forty-five thousand, thirty-one".