28220667091 has 2 divisors, whose sum is σ = 28220667092. Its totient is φ = 28220667090.

The previous prime is 28220667043. The next prime is 28220667133. The reversal of 28220667091 is 19076602282.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28220667091 - 2²³ = 28212278483 is a prime.

It is a super-2 number, since 2×28220667091² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28220667031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14110333545 + 14110333546.

It is an arithmetic number, because the mean of its divisors is an integer number (14110333546).

Almost surely, 2^28220667091 is an apocalyptic number.

28220667091 is a deficient number, since it is larger than the sum of its proper divisors (1).

28220667091 is an equidigital number, since it uses as much as digits as its factorization.

28220667091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 43.

The spelling of 28220667091 in words is "twenty-eight billion, two hundred twenty million, six hundred sixty-seven thousand, ninety-one".