1612065661 has 4 divisors (see below), whose sum is σ = 1612297152. Its totient is φ = 1611834172.

The previous prime is 1612065619. The next prime is 1612065713. The reversal of 1612065661 is 1665602161.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 1612065661 - 2¹⁵ = 1612032893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1612065061) 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, 104965 + ... + 119338.

It is an arithmetic number, because the mean of its divisors is an integer number (403074288).

Almost surely, 2^1612065661 is an apocalyptic number.

It is an amenable number.

1612065661 is a deficient number, since it is larger than the sum of its proper divisors (231491).

1612065661 is an equidigital number, since it uses as much as digits as its factorization.

1612065661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231490.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 1612065661 is about 40150.5374932889. The cubic root of 1612065661 is about 1172.5397530632.

The spelling of 1612065661 in words is "one billion, six hundred twelve million, sixty-five thousand, six hundred sixty-one".