99951881 has 2 divisors, whose sum is σ = 99951882. Its totient is φ = 99951880.

The previous prime is 99951877. The next prime is 99951889. The reversal of 99951881 is 18815999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 82646281 + 17305600 = 9091^2 + 4160^2 .

It is a cyclic number.

It is not a de Polignac number, because 99951881 - 2² = 99951877 is a prime.

It is a super-2 number, since 2×99951881² = 19980757030876322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (99951889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49975940 + 49975941.

It is an arithmetic number, because the mean of its divisors is an integer number (49975941).

Almost surely, 2^99951881 is an apocalyptic number.

It is an amenable number.

99951881 is a deficient number, since it is larger than the sum of its proper divisors (1).

99951881 is an equidigital number, since it uses as much as digits as its factorization.

99951881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 50.

The square root of 99951881 is about 9997.5937605006. The cubic root of 99951881 is about 464.0844218789.

The spelling of 99951881 in words is "ninety-nine million, nine hundred fifty-one thousand, eight hundred eighty-one".