28896920957 has 4 divisors (see below), whose sum is σ = 29056572636. Its totient is φ = 28737269280.

The previous prime is 28896920953. The next prime is 28896920959. The reversal of 28896920957 is 75902969882.

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

It can be written as a sum of positive squares in 2 ways, for example, as 178195801 + 28718725156 = 13349^2 + 169466^2 .

It is a cyclic number.

It is not a de Polignac number, because 28896920957 - 2² = 28896920953 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28896920893 and 28896920902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28896920953) 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, 79825568 + ... + 79825929.

It is an arithmetic number, because the mean of its divisors is an integer number (7264143159).

Almost surely, 2^28896920957 is an apocalyptic number.

It is an amenable number.

28896920957 is a deficient number, since it is larger than the sum of its proper divisors (159651679).

28896920957 is a wasteful number, since it uses less digits than its factorization.

28896920957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159651678.

The product of its (nonzero) digits is 39191040, while the sum is 65.

The spelling of 28896920957 in words is "twenty-eight billion, eight hundred ninety-six million, nine hundred twenty thousand, nine hundred fifty-seven".