1600501661 has 4 divisors (see below), whose sum is σ = 1746001824. Its totient is φ = 1455001500.

The previous prime is 1600501657. The next prime is 1600501709. The reversal of 1600501661 is 1661050061.

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 1600501661 - 2² = 1600501657 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 1600501661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1600501061) 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, 72750065 + ... + 72750086.

It is an arithmetic number, because the mean of its divisors is an integer number (436500456).

Almost surely, 2^1600501661 is an apocalyptic number.

1600501661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1600501661 is a deficient number, since it is larger than the sum of its proper divisors (145500163).

1600501661 is a wasteful number, since it uses less digits than its factorization.

1600501661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145500162.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 1600501661 is about 40006.2702710463. The cubic root of 1600501661 is about 1169.7293213171.

The spelling of 1600501661 in words is "one billion, six hundred million, five hundred one thousand, six hundred sixty-one".