66663955 has 4 divisors (see below), whose sum is σ = 79996752. Its totient is φ = 53331160.

The previous prime is 66663931. The next prime is 66663967. The reversal of 66663955 is 55936666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55936666 = 2 ⋅27968333.

It is a de Polignac number, because none of the positive numbers 2^k-66663955 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6666391 + ... + 6666400.

It is an arithmetic number, because the mean of its divisors is an integer number (19999188).

Almost surely, 2^66663955 is an apocalyptic number.

66663955 is a deficient number, since it is larger than the sum of its proper divisors (13332797).

66663955 is a wasteful number, since it uses less digits than its factorization.

66663955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13332796.

The product of its digits is 874800, while the sum is 46.

The square root of 66663955 is about 8164.7997525965. The cubic root of 66663955 is about 405.4746353289.

The spelling of 66663955 in words is "sixty-six million, six hundred sixty-three thousand, nine hundred fifty-five".