28572661 has 6 divisors (see below), whose sum is σ = 30939810. Its totient is φ = 26374608.

The previous prime is 28572623. The next prime is 28572679. The reversal of 28572661 is 16627582.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 280900 + 28291761 = 530^2 + 5319^2 .

It is not a de Polignac number, because 28572661 - 2⁹ = 28572149 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 28572661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28578661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 84366 + ... + 84703.

It is an arithmetic number, because the mean of its divisors is an integer number (5156635).

Almost surely, 2^28572661 is an apocalyptic number.

It is an amenable number.

28572661 is a deficient number, since it is larger than the sum of its proper divisors (2367149).

28572661 is a wasteful number, since it uses less digits than its factorization.

28572661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169095 (or 169082 counting only the distinct ones).

The product of its digits is 40320, while the sum is 37.

The square root of 28572661 is about 5345.3401201420. The cubic root of 28572661 is about 305.7151042802.

The spelling of 28572661 in words is "twenty-eight million, five hundred seventy-two thousand, six hundred sixty-one".