56666161 has 4 divisors (see below), whose sum is σ = 57871872. Its totient is φ = 55460452.

The previous prime is 56666149. The next prime is 56666173. The reversal of 56666161 is 16166665.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16166665 = 5 ⋅3233333.

It is an interprime number because it is at equal distance from previous prime (56666149) and next prime (56666173).

It is a cyclic number.

It is not a de Polignac number, because 56666161 - 2¹³ = 56657969 is a prime.

It is a super-2 number, since 2×56666161² = 6422107604955842, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 56666161.

It is not an unprimeable number, because it can be changed into a prime (56666111) 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, 602785 + ... + 602878.

It is an arithmetic number, because the mean of its divisors is an integer number (14467968).

Almost surely, 2^56666161 is an apocalyptic number.

It is an amenable number.

56666161 is a deficient number, since it is larger than the sum of its proper divisors (1205711).

56666161 is a wasteful number, since it uses less digits than its factorization.

56666161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1205710.

The product of its digits is 38880, while the sum is 37.

The square root of 56666161 is about 7527.6929400713. The cubic root of 56666161 is about 384.0973083290.

The spelling of 56666161 in words is "fifty-six million, six hundred sixty-six thousand, one hundred sixty-one".