1721774561 has 8 divisors (see below), whose sum is σ = 1854569640. Its totient is φ = 1589029632.

The previous prime is 1721774543. The next prime is 1721774597. The reversal of 1721774561 is 1654771271.

It can be written as a sum of positive squares in 4 ways, for example, as 61701025 + 1660073536 = 7855^2 + 40744^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1721774561 - 2⁶ = 1721774497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1721774531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89705 + ... + 107193.

It is an arithmetic number, because the mean of its divisors is an integer number (231821205).

Almost surely, 2^1721774561 is an apocalyptic number.

It is an amenable number.

1721774561 is a deficient number, since it is larger than the sum of its proper divisors (132795079).

1721774561 is a wasteful number, since it uses less digits than its factorization.

1721774561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25075.

The product of its digits is 82320, while the sum is 41.

The square root of 1721774561 is about 41494.2714238966. The cubic root of 1721774561 is about 1198.5571921071.

The spelling of 1721774561 in words is "one billion, seven hundred twenty-one million, seven hundred seventy-four thousand, five hundred sixty-one".