66806408 has 16 divisors (see below), whose sum is σ = 127386000. Its totient is φ = 32836816.

The previous prime is 66806387. The next prime is 66806431. The reversal of 66806408 is 80460866.

It is a super-2 number, since 2×66806408² = 8926192299724928, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70298 + ... + 71241.

It is an arithmetic number, because the mean of its divisors is an integer number (7961625).

Almost surely, 2^66806408 is an apocalyptic number.

It is an amenable number.

66806408 is a deficient number, since it is larger than the sum of its proper divisors (60579592).

66806408 is a wasteful number, since it uses less digits than its factorization.

66806408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141604 (or 141600 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 38.

The square root of 66806408 is about 8173.5187037163. The cubic root of 66806408 is about 405.7632469888.

The spelling of 66806408 in words is "sixty-six million, eight hundred six thousand, four hundred eight".