66869878 has 32 divisors (see below), whose sum is σ = 108838080. Its totient is φ = 30729600.

The previous prime is 66869839. The next prime is 66869879. The reversal of 66869878 is 87896866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66869879) 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, 171708 + ... + 172096.

It is an arithmetic number, because the mean of its divisors is an integer number (3401190).

Almost surely, 2^66869878 is an apocalyptic number.

66869878 is a deficient number, since it is larger than the sum of its proper divisors (41968202).

66869878 is a wasteful number, since it uses less digits than its factorization.

66869878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552.

The product of its digits is 6967296, while the sum is 58.

The square root of 66869878 is about 8177.4004426835. The cubic root of 66869878 is about 405.8917059321.

The spelling of 66869878 in words is "sixty-six million, eight hundred sixty-nine thousand, eight hundred seventy-eight".