1656650161 has 4 divisors (see below), whose sum is σ = 1660604400. Its totient is φ = 1652695924.

The previous prime is 1656650159. The next prime is 1656650179. The reversal of 1656650161 is 1610566561.

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: 1610566561 = 547 ⋅2944363.

It is a cyclic number.

It is not a de Polignac number, because 1656650161 - 2¹ = 1656650159 is a prime.

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 1656650161.

It is not an unprimeable number, because it can be changed into a prime (1656650131) 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, 1976491 + ... + 1977328.

It is an arithmetic number, because the mean of its divisors is an integer number (415151100).

Almost surely, 2^1656650161 is an apocalyptic number.

It is an amenable number.

1656650161 is a deficient number, since it is larger than the sum of its proper divisors (3954239).

1656650161 is an equidigital number, since it uses as much as digits as its factorization.

1656650161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3954238.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 1656650161 is about 40701.9675322950. The cubic root of 1656650161 is about 1183.2511512236.

The spelling of 1656650161 in words is "one billion, six hundred fifty-six million, six hundred fifty thousand, one hundred sixty-one".