28901681647 has 4 divisors (see below), whose sum is σ = 29682808216. Its totient is φ = 28120555080.

The previous prime is 28901681639. The next prime is 28901681651. The reversal of 28901681647 is 74618610982.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28901681647 - 2³ = 28901681639 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28901681594 and 28901681603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28901681617) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 390563229 + ... + 390563302.

It is an arithmetic number, because the mean of its divisors is an integer number (7420702054).

Almost surely, 2^28901681647 is an apocalyptic number.

28901681647 is a deficient number, since it is larger than the sum of its proper divisors (781126569).

28901681647 is an equidigital number, since it uses as much as digits as its factorization.

28901681647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781126568.

The product of its (nonzero) digits is 1161216, while the sum is 52.

The spelling of 28901681647 in words is "twenty-eight billion, nine hundred one million, six hundred eighty-one thousand, six hundred forty-seven".