99991249 has 2 divisors, whose sum is σ = 99991250. Its totient is φ = 99991248.

The previous prime is 99991237. The next prime is 99991271. The reversal of 99991249 is 94219999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72795024 + 27196225 = 8532^2 + 5215^2 .

It is a cyclic number.

It is not a de Polignac number, because 99991249 - 2¹³ = 99983057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 99991196 and 99991205.

It is not a weakly prime, because it can be changed into another prime (99991049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49995624 + 49995625.

It is an arithmetic number, because the mean of its divisors is an integer number (49995625).

Almost surely, 2^99991249 is an apocalyptic number.

It is an amenable number.

99991249 is a deficient number, since it is larger than the sum of its proper divisors (1).

99991249 is an equidigital number, since it uses as much as digits as its factorization.

99991249 is an evil number, because the sum of its binary digits is even.

The product of its digits is 472392, while the sum is 52.

The square root of 99991249 is about 9999.5624404271. The cubic root of 99991249 is about 464.1453434517.

The spelling of 99991249 in words is "ninety-nine million, nine hundred ninety-one thousand, two hundred forty-nine".