66920945 has 32 divisors (see below), whose sum is σ = 104052480. Its totient is φ = 40124160.

The previous prime is 66920941. The next prime is 66920963. The reversal of 66920945 is 54902966.

It is not a de Polignac number, because 66920945 - 2² = 66920941 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66920941) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4775 + ... + 12515.

It is an arithmetic number, because the mean of its divisors is an integer number (3251640).

Almost surely, 2^66920945 is an apocalyptic number.

66920945 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66920945 is a deficient number, since it is larger than the sum of its proper divisors (37131535).

66920945 is a wasteful number, since it uses less digits than its factorization.

66920945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7785.

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 66920945 is about 8180.5222938392. The cubic root of 66920945 is about 405.9950030527.

The spelling of 66920945 in words is "sixty-six million, nine hundred twenty thousand, nine hundred forty-five".