66931345 has 16 divisors (see below), whose sum is σ = 87720192. Its totient is φ = 48726720.

The previous prime is 66931343. The next prime is 66931351. The reversal of 66931345 is 54313966.

It is not a de Polignac number, because 66931345 - 2¹ = 66931343 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66931343) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2637 + ... + 11866.

It is an arithmetic number, because the mean of its divisors is an integer number (5482512).

Almost surely, 2^66931345 is an apocalyptic number.

66931345 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66931345 is a deficient number, since it is larger than the sum of its proper divisors (20788847).

66931345 is a wasteful number, since it uses less digits than its factorization.

66931345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14592.

The product of its digits is 58320, while the sum is 37.

The square root of 66931345 is about 8181.1579253795. The cubic root of 66931345 is about 406.0160334856.

It can be divided in two parts, 66931 and 345, that added together give a palindrome (67276).

The spelling of 66931345 in words is "sixty-six million, nine hundred thirty-one thousand, three hundred forty-five".