66531955 has 24 divisors (see below), whose sum is σ = 93234672. Its totient is φ = 45444672.

The previous prime is 66531943. The next prime is 66531961. The reversal of 66531955 is 55913566.

It is not a de Polignac number, because 66531955 - 2¹¹ = 66529907 is a prime.

It is a super-2 number, since 2×66531955² = 8853002072244050, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 108229 + ... + 108841.

It is an arithmetic number, because the mean of its divisors is an integer number (3884778).

Almost surely, 2^66531955 is an apocalyptic number.

66531955 is a deficient number, since it is larger than the sum of its proper divisors (26702717).

66531955 is a wasteful number, since it uses less digits than its factorization.

66531955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1075 (or 1068 counting only the distinct ones).

The product of its digits is 121500, while the sum is 40.

The square root of 66531955 is about 8156.7122665937. The cubic root of 66531955 is about 405.2068343503.

The spelling of 66531955 in words is "sixty-six million, five hundred thirty-one thousand, nine hundred fifty-five".