28720344697 has 16 divisors (see below), whose sum is σ = 34616668032. Its totient is φ = 23505137920.

The previous prime is 28720344689. The next prime is 28720344701. The reversal of 28720344697 is 79644302782.

It is not a de Polignac number, because 28720344697 - 2³ = 28720344689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28720344997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3334498 + ... + 3343099.

It is an arithmetic number, because the mean of its divisors is an integer number (2163541752).

Almost surely, 2^28720344697 is an apocalyptic number.

It is an amenable number.

28720344697 is a deficient number, since it is larger than the sum of its proper divisors (5896323335).

28720344697 is a wasteful number, since it uses less digits than its factorization.

28720344697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6677648.

The product of its (nonzero) digits is 4064256, while the sum is 52.

The spelling of 28720344697 in words is "twenty-eight billion, seven hundred twenty million, three hundred forty-four thousand, six hundred ninety-seven".