2457921 has 4 divisors (see below), whose sum is σ = 3277232. Its totient is φ = 1638612.

The previous prime is 2457901. The next prime is 2457943. The reversal of 2457921 is 1297542.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2457921 - 2¹³ = 2449729 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2457901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 409651 + ... + 409656.

It is an arithmetic number, because the mean of its divisors is an integer number (819308).

2^2457921 is an apocalyptic number.

It is an amenable number.

2457921 is a deficient number, since it is larger than the sum of its proper divisors (819311).

2457921 is an equidigital number, since it uses as much as digits as its factorization.

2457921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 819310.

The product of its digits is 5040, while the sum is 30.

The square root of 2457921 is about 1567.7758130549. The cubic root of 2457921 is about 134.9551016674.

The spelling of 2457921 in words is "two million, four hundred fifty-seven thousand, nine hundred twenty-one".