28073545921 has 2 divisors, whose sum is σ = 28073545922. Its totient is φ = 28073545920.

The previous prime is 28073545883. The next prime is 28073545943. The reversal of 28073545921 is 12954537082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19027443600 + 9046102321 = 137940^2 + 95111^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28073545921 is a prime.

It is not a weakly prime, because it can be changed into another prime (28073540921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14036772960 + 14036772961.

It is an arithmetic number, because the mean of its divisors is an integer number (14036772961).

Almost surely, 2^28073545921 is an apocalyptic number.

It is an amenable number.

28073545921 is a deficient number, since it is larger than the sum of its proper divisors (1).

28073545921 is an equidigital number, since it uses as much as digits as its factorization.

28073545921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 28073545921 in words is "twenty-eight billion, seventy-three million, five hundred forty-five thousand, nine hundred twenty-one".