66578157 has 12 divisors (see below), whose sum is σ = 96318144. Its totient is φ = 44316360.

The previous prime is 66578153. The next prime is 66578159. The reversal of 66578157 is 75187566.

66578157 is a `hidden beast` number, since 66 + 578 + 15 + 7 = 666.

It is not a de Polignac number, because 66578157 - 2² = 66578153 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66578153) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 732 + ... + 11562.

It is an arithmetic number, because the mean of its divisors is an integer number (8026512).

Almost surely, 2^66578157 is an apocalyptic number.

It is an amenable number.

66578157 is a deficient number, since it is larger than the sum of its proper divisors (29739987).

66578157 is a wasteful number, since it uses less digits than its factorization.

66578157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11520 (or 11517 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 66578157 is about 8159.5439210779. The cubic root of 66578157 is about 405.3006090096.

The spelling of 66578157 in words is "sixty-six million, five hundred seventy-eight thousand, one hundred fifty-seven".