2517921 has 24 divisors (see below), whose sum is σ = 4402944. Its totient is φ = 1353600.

The previous prime is 2517919. The next prime is 2517929. The reversal of 2517921 is 1297152.

2517921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2517921 - 2¹ = 2517919 is a prime.

It is a Curzon number.

2517921 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2517929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 105 + ... + 2246.

It is an arithmetic number, because the mean of its divisors is an integer number (183456).

2^2517921 is an apocalyptic number.

2517921 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2517921 is a deficient number, since it is larger than the sum of its proper divisors (1885023).

2517921 is a wasteful number, since it uses less digits than its factorization.

2517921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2381 (or 2378 counting only the distinct ones).

The product of its digits is 1260, while the sum is 27.

The square root of 2517921 is about 1586.7958280762. The cubic root of 2517921 is about 136.0444095165.

It can be divided in two parts, 25179 and 21, that added together give a triangular number (25200 = T₂₂₄).

The spelling of 2517921 in words is "two million, five hundred seventeen thousand, nine hundred twenty-one".