28465521989 has 2 divisors, whose sum is σ = 28465521990. Its totient is φ = 28465521988.

The previous prime is 28465521923. The next prime is 28465522003. The reversal of 28465521989 is 98912556482.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18675408964 + 9790113025 = 136658^2 + 98945^2 .

It is a cyclic number.

It is not a de Polignac number, because 28465521989 - 2²⁴ = 28448744773 is a prime.

It is a super-2 number, since 2×28465521989² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28465520989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14232760994 + 14232760995.

It is an arithmetic number, because the mean of its divisors is an integer number (14232760995).

Almost surely, 2^28465521989 is an apocalyptic number.

It is an amenable number.

28465521989 is a deficient number, since it is larger than the sum of its proper divisors (1).

28465521989 is an equidigital number, since it uses as much as digits as its factorization.

28465521989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12441600, while the sum is 59.

The spelling of 28465521989 in words is "twenty-eight billion, four hundred sixty-five million, five hundred twenty-one thousand, nine hundred eighty-nine".