28601601665 has 32 divisors (see below), whose sum is σ = 42276003840. Its totient is φ = 18089455104.

The previous prime is 28601601629. The next prime is 28601601667. The reversal of 28601601665 is 56610610682.

It is a happy number.

It is not a de Polignac number, because 28601601665 - 2⁸ = 28601601409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28601601667) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 562112 + ... + 610878.

It is an arithmetic number, because the mean of its divisors is an integer number (1321125120).

Almost surely, 2^28601601665 is an apocalyptic number.

It is an amenable number.

28601601665 is a deficient number, since it is larger than the sum of its proper divisors (13674402175).

28601601665 is a wasteful number, since it uses less digits than its factorization.

28601601665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50081.

The product of its (nonzero) digits is 103680, while the sum is 41.

The spelling of 28601601665 in words is "twenty-eight billion, six hundred one million, six hundred one thousand, six hundred sixty-five".