28572991 has 8 divisors (see below), whose sum is σ = 29415344. Its totient is φ = 27734400.

The previous prime is 28572983. The next prime is 28573009. The reversal of 28572991 is 19927582.

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 28572991 - 2³ = 28572983 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 (28572191) 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 7 ways as a sum of consecutive naturals, for example, 23191 + ... + 24391.

It is an arithmetic number, because the mean of its divisors is an integer number (3676918).

Almost surely, 2^28572991 is an apocalyptic number.

28572991 is a deficient number, since it is larger than the sum of its proper divisors (842353).

28572991 is a wasteful number, since it uses less digits than its factorization.

28572991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1881.

The product of its digits is 90720, while the sum is 43.

The square root of 28572991 is about 5345.3709880606. The cubic root of 28572991 is about 305.7162812280.

The spelling of 28572991 in words is "twenty-eight million, five hundred seventy-two thousand, nine hundred ninety-one".