1915 has 4 divisors (see below), whose sum is σ = 2304. Its totient is φ = 1528.

The previous prime is 1913. The next prime is 1931. The reversal of 1915 is 5191.

1915 is an esthetic number in base 14, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5191 = 29 ⋅179.

It is a cyclic number.

It is not a de Polignac number, because 1915 - 2¹ = 1913 is a prime.

It is a Duffinian number.

1915 is a lucky number.

It is a plaindrome in base 9, base 12, base 14 and base 16.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (1913) 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, 187 + ... + 196.

It is an arithmetic number, because the mean of its divisors is an integer number (576).

1915 is a deficient number, since it is larger than the sum of its proper divisors (389).

1915 is an equidigital number, since it uses as much as digits as its factorization.

1915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 388.

The product of its digits is 45, while the sum is 16.

The square root of 1915 is about 43.7607129741. The cubic root of 1915 is about 12.4181316430.

It can be divided in two parts, 191 and 5, that added together give a square (196 = 14²).

The spelling of 1915 in words is "one thousand, nine hundred fifteen".