2091145997 has 6 divisors (see below), whose sum is σ = 2097483498. Its totient is φ = 2084827584.

The previous prime is 2091145967. The next prime is 2091146011. The reversal of 2091145997 is 7995411902.

It can be written as a sum of positive squares in 3 ways, for example, as 1833316 + 2089312681 = 1354^2 + 45709^2 .

It is not a de Polignac number, because 2091145997 - 2⁶ = 2091145933 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 (2091145937) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 104363 + ... + 122775.

It is an arithmetic number, because the mean of its divisors is an integer number (349580583).

Almost surely, 2^2091145997 is an apocalyptic number.

It is an amenable number.

2091145997 is a deficient number, since it is larger than the sum of its proper divisors (6337501).

2091145997 is an frugal number, since it uses more digits than its factorization.

2091145997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19087 (or 18750 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 47.

The square root of 2091145997 is about 45729.0498151886. The cubic root of 2091145997 is about 1278.7769072182.

The spelling of 2091145997 in words is "two billion, ninety-one million, one hundred forty-five thousand, nine hundred ninety-seven".