99978465589 has 2 divisors, whose sum is σ = 99978465590. Its totient is φ = 99978465588.

The previous prime is 99978465547. The next prime is 99978465593. The reversal of 99978465589 is 98556487999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87981644689 + 11996820900 = 296617^2 + 109530^2 .

It is a cyclic number.

It is not a de Polignac number, because 99978465589 - 2³⁵ = 65618727221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99978465539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49989232794 + 49989232795.

It is an arithmetic number, because the mean of its divisors is an integer number (49989232795).

Almost surely, 2^99978465589 is an apocalyptic number.

It is an amenable number.

99978465589 is a deficient number, since it is larger than the sum of its proper divisors (1).

99978465589 is an equidigital number, since it uses as much as digits as its factorization.

99978465589 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1763596800, while the sum is 79.

The spelling of 99978465589 in words is "ninety-nine billion, nine hundred seventy-eight million, four hundred sixty-five thousand, five hundred eighty-nine".