28401565 has 8 divisors (see below), whose sum is σ = 34225920. Its totient is φ = 22625232.

The previous prime is 28401557. The next prime is 28401589. The reversal of 28401565 is 56510482.

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 28401565 - 2³ = 28401557 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10689 + ... + 13078.

It is an arithmetic number, because the mean of its divisors is an integer number (4278240).

Almost surely, 2^28401565 is an apocalyptic number.

It is an amenable number.

28401565 is a deficient number, since it is larger than the sum of its proper divisors (5824355).

28401565 is a wasteful number, since it uses less digits than its factorization.

28401565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24011.

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 28401565 is about 5329.3118692754. The cubic root of 28401565 is about 305.1036644845.

The spelling of 28401565 in words is "twenty-eight million, four hundred one thousand, five hundred sixty-five".