991749103 has 2 divisors, whose sum is σ = 991749104. Its totient is φ = 991749102.

The previous prime is 991749097. The next prime is 991749107. The reversal of 991749103 is 301947199.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 991749103 - 2¹⁷ = 991618031 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 991749103.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991749107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495874551 + 495874552.

It is an arithmetic number, because the mean of its divisors is an integer number (495874552).

Almost surely, 2^991749103 is an apocalyptic number.

991749103 is a deficient number, since it is larger than the sum of its proper divisors (1).

991749103 is an equidigital number, since it uses as much as digits as its factorization.

991749103 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 991749103 is about 31492.0482503123. The cubic root of 991749103 is about 997.2421019908.

The spelling of 991749103 in words is "nine hundred ninety-one million, seven hundred forty-nine thousand, one hundred three".