571220661 has 16 divisors (see below), whose sum is σ = 835849728. Its totient is φ = 344118000.

The previous prime is 571220659. The next prime is 571220707. The reversal of 571220661 is 166022175.

It is not a de Polignac number, because 571220661 - 2¹ = 571220659 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (571220861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46315 + ... + 57336.

It is an arithmetic number, because the mean of its divisors is an integer number (52240608).

Almost surely, 2^571220661 is an apocalyptic number.

It is an amenable number.

571220661 is a deficient number, since it is larger than the sum of its proper divisors (264629067).

571220661 is a wasteful number, since it uses less digits than its factorization.

571220661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103832.

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 571220661 is about 23900.2230324321. The cubic root of 571220661 is about 829.7258788968.

The spelling of 571220661 in words is "five hundred seventy-one million, two hundred twenty thousand, six hundred sixty-one".