99844146781 has 2 divisors, whose sum is σ = 99844146782. Its totient is φ = 99844146780.

The previous prime is 99844146763. The next prime is 99844146811. The reversal of 99844146781 is 18764144899.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62075722500 + 37768424281 = 249150^2 + 194341^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99844146781 is a prime.

It is a super-2 number, since 2×99844146781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99844141781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49922073390 + 49922073391.

It is an arithmetic number, because the mean of its divisors is an integer number (49922073391).

Almost surely, 2^99844146781 is an apocalyptic number.

It is an amenable number.

99844146781 is a deficient number, since it is larger than the sum of its proper divisors (1).

99844146781 is an equidigital number, since it uses as much as digits as its factorization.

99844146781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13934592, while the sum is 61.

The spelling of 99844146781 in words is "ninety-nine billion, eight hundred forty-four million, one hundred forty-six thousand, seven hundred eighty-one".