66631945 has 8 divisors (see below), whose sum is σ = 81313920. Its totient is φ = 52401840.

The previous prime is 66631933. The next prime is 66631963. The reversal of 66631945 is 54913666.

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

It is not a de Polignac number, because 66631945 - 2⁵ = 66631913 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66631898 and 66631907.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112641 + ... + 113230.

It is an arithmetic number, because the mean of its divisors is an integer number (10164240).

Almost surely, 2^66631945 is an apocalyptic number.

It is an amenable number.

66631945 is a deficient number, since it is larger than the sum of its proper divisors (14681975).

66631945 is a wasteful number, since it uses less digits than its factorization.

66631945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225935.

The product of its digits is 116640, while the sum is 40.

The square root of 66631945 is about 8162.8392731941. The cubic root of 66631945 is about 405.4097260835.

It can be divided in two parts, 66631 and 945, that added together give a palindrome (67576).

The spelling of 66631945 in words is "sixty-six million, six hundred thirty-one thousand, nine hundred forty-five".