1991022103 has 8 divisors (see below), whose sum is σ = 2395214720. Its totient is φ = 1616769720.

The previous prime is 1991022101. The next prime is 1991022107. The reversal of 1991022103 is 3012201991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1991022103 - 2¹ = 1991022101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991022101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7484913 + ... + 7485178.

It is an arithmetic number, because the mean of its divisors is an integer number (299401840).

Almost surely, 2^1991022103 is an apocalyptic number.

1991022103 is a deficient number, since it is larger than the sum of its proper divisors (404192617).

1991022103 is a wasteful number, since it uses less digits than its factorization.

1991022103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14970117.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 1991022103 is about 44620.8707109128. The cubic root of 1991022103 is about 1258.0329816877.

The spelling of 1991022103 in words is "one billion, nine hundred ninety-one million, twenty-two thousand, one hundred three".