28250646491 has 4 divisors (see below), whose sum is σ = 28253257032. Its totient is φ = 28248035952.

The previous prime is 28250646469. The next prime is 28250646499. The reversal of 28250646491 is 19464605282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19464605282 = 2 ⋅9732302641.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28250646491 is a prime.

It is a super-2 number, since 2×28250646491² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28250646499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1288970 + ... + 1310703.

It is an arithmetic number, because the mean of its divisors is an integer number (7063314258).

Almost surely, 2^28250646491 is an apocalyptic number.

28250646491 is a deficient number, since it is larger than the sum of its proper divisors (2610541).

28250646491 is a wasteful number, since it uses less digits than its factorization.

28250646491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2610540.

The product of its (nonzero) digits is 829440, while the sum is 47.

The spelling of 28250646491 in words is "twenty-eight billion, two hundred fifty million, six hundred forty-six thousand, four hundred ninety-one".