66550879 has 4 divisors (see below), whose sum is σ = 67678920. Its totient is φ = 65422840.

The previous prime is 66550871. The next prime is 66550889. The reversal of 66550879 is 97805566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97805566 = 2 ⋅48902783.

It is a cyclic number.

It is not a de Polignac number, because 66550879 - 2³ = 66550871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66550871) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 563932 + ... + 564049.

It is an arithmetic number, because the mean of its divisors is an integer number (16919730).

Almost surely, 2^66550879 is an apocalyptic number.

66550879 is a deficient number, since it is larger than the sum of its proper divisors (1128041).

66550879 is a wasteful number, since it uses less digits than its factorization.

66550879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1128040.

The product of its (nonzero) digits is 453600, while the sum is 46.

The square root of 66550879 is about 8157.8722103254. The cubic root of 66550879 is about 405.2452490099.

The spelling of 66550879 in words is "sixty-six million, five hundred fifty thousand, eight hundred seventy-nine".