99606781 has 2 divisors, whose sum is σ = 99606782. Its totient is φ = 99606780.

The previous prime is 99606761. The next prime is 99606827. The reversal of 99606781 is 18760699.

It is an a-pointer prime, because the next prime (99606827) can be obtained adding 99606781 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 93431556 + 6175225 = 9666^2 + 2485^2 .

It is an emirp because it is prime and its reverse (18760699) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99606781 - 2¹¹ = 99604733 is a prime.

It is a super-2 number, since 2×99606781² = 19843021642363922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99606761) 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, 49803390 + 49803391.

It is an arithmetic number, because the mean of its divisors is an integer number (49803391).

Almost surely, 2^99606781 is an apocalyptic number.

It is an amenable number.

99606781 is a deficient number, since it is larger than the sum of its proper divisors (1).

99606781 is an equidigital number, since it uses as much as digits as its factorization.

99606781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 163296, while the sum is 46.

The square root of 99606781 is about 9980.3196842586. The cubic root of 99606781 is about 463.5496972104.

The spelling of 99606781 in words is "ninety-nine million, six hundred six thousand, seven hundred eighty-one".