66879995 has 16 divisors (see below), whose sum is σ = 98777280. Its totient is φ = 42332544.

The previous prime is 66879977. The next prime is 66879997. The reversal of 66879995 is 59997866.

66879995 = 3088² + 3089² + ... + 3094².

It is a cyclic number.

It is not a de Polignac number, because 66879995 - 2¹⁰ = 66878971 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66879997) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 73040 + ... + 73949.

It is an arithmetic number, because the mean of its divisors is an integer number (6173580).

Almost surely, 2^66879995 is an apocalyptic number.

66879995 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66879995 is a deficient number, since it is larger than the sum of its proper divisors (31897285).

66879995 is a wasteful number, since it uses less digits than its factorization.

66879995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147014.

The product of its digits is 7348320, while the sum is 59.

The square root of 66879995 is about 8178.0190144069. The cubic root of 66879995 is about 405.9121745368.

The spelling of 66879995 in words is "sixty-six million, eight hundred seventy-nine thousand, nine hundred ninety-five".