66947405 has 16 divisors (see below), whose sum is σ = 93187200. Its totient is φ = 45220032.

The previous prime is 66947369. The next prime is 66947437. The reversal of 66947405 is 50474966.

It is a cyclic number.

It is not a de Polignac number, because 66947405 - 2²⁰ = 65898829 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11930 + ... + 16619.

It is an arithmetic number, because the mean of its divisors is an integer number (5824200).

Almost surely, 2^66947405 is an apocalyptic number.

It is an amenable number.

66947405 is a deficient number, since it is larger than the sum of its proper divisors (26239795).

66947405 is a wasteful number, since it uses less digits than its factorization.

66947405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28628.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 66947405 is about 8182.1393901595. The cubic root of 66947405 is about 406.0485050479.

The spelling of 66947405 in words is "sixty-six million, nine hundred forty-seven thousand, four hundred five".