56666578 has 4 divisors (see below), whose sum is σ = 84999870. Its totient is φ = 28333288.

The previous prime is 56666563. The next prime is 56666579. The reversal of 56666578 is 87566665.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87566665 = 5 ⋅17513333.

It can be written as a sum of positive squares in only one way, i.e., 44395569 + 12271009 = 6663^2 + 3503^2 .

It is a super-2 number, since 2×56666578² = 6422202124460168, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (56666579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14166643 + ... + 14166646.

Almost surely, 2^56666578 is an apocalyptic number.

56666578 is a deficient number, since it is larger than the sum of its proper divisors (28333292).

56666578 is a wasteful number, since it uses less digits than its factorization.

56666578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28333291.

The product of its digits is 1814400, while the sum is 49.

The square root of 56666578 is about 7527.7206377495. The cubic root of 56666578 is about 384.0982505032.

It can be divided in two parts, 5666657 and 8, that added together give a palindrome (5666665).

The spelling of 56666578 in words is "fifty-six million, six hundred sixty-six thousand, five hundred seventy-eight".