1664560161 has 24 divisors (see below), whose sum is σ = 2627876160. Its totient is φ = 1006927200.

The previous prime is 1664560153. The next prime is 1664560169. The reversal of 1664560161 is 1610654661.

It is a happy number.

1664560161 is a `hidden beast` number, since 1 + 6 + 6 + 45 + 601 + 6 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (1664560153) and next prime (1664560169).

It is not a de Polignac number, because 1664560161 - 2³ = 1664560153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1664560169) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38020 + ... + 69098.

It is an arithmetic number, because the mean of its divisors is an integer number (109494840).

Almost surely, 2^1664560161 is an apocalyptic number.

1664560161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1664560161 is a deficient number, since it is larger than the sum of its proper divisors (963315999).

1664560161 is a wasteful number, since it uses less digits than its factorization.

1664560161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31637 (or 31634 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 1664560161 is about 40799.0215691504. The cubic root of 1664560161 is about 1185.1313831788.

The spelling of 1664560161 in words is "one billion, six hundred sixty-four million, five hundred sixty thousand, one hundred sixty-one".