1915500001 has 4 divisors (see below), whose sum is σ = 1915587604. Its totient is φ = 1915412400.

The previous prime is 1915499941. The next prime is 1915500017. The reversal of 1915500001 is 1000055191.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1000055191 = 2467 ⋅405373.

It can be written as a sum of positive squares in 2 ways, for example, as 1161173776 + 754326225 = 34076^2 + 27465^2 .

It is a cyclic number.

It is not a de Polignac number, because 1915500001 - 2⁹ = 1915499489 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (1915500061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19291 + ... + 64831.

It is an arithmetic number, because the mean of its divisors is an integer number (478896901).

Almost surely, 2^1915500001 is an apocalyptic number.

It is an amenable number.

1915500001 is a deficient number, since it is larger than the sum of its proper divisors (87603).

1915500001 is an equidigital number, since it uses as much as digits as its factorization.

1915500001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87602.

The product of its (nonzero) digits is 225, while the sum is 22.

The square root of 1915500001 is about 43766.4254994625. The cubic root of 1915500001 is about 1241.9212328486.

Adding to 1915500001 its reverse (1000055191), we get a palindrome (2915555192).

The spelling of 1915500001 in words is "one billion, nine hundred fifteen million, five hundred thousand, one".