2391421 has 4 divisors (see below), whose sum is σ = 2456092. Its totient is φ = 2326752.

The previous prime is 2391401. The next prime is 2391437. The reversal of 2391421 is 1241932.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1768900 + 622521 = 1330^2 + 789^2 .

It is a cyclic number.

It is not a de Polignac number, because 2391421 - 2⁷ = 2391293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2391392 and 2391401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2391401) 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, 32280 + ... + 32353.

It is an arithmetic number, because the mean of its divisors is an integer number (614023).

2^2391421 is an apocalyptic number.

It is an amenable number.

2391421 is a deficient number, since it is larger than the sum of its proper divisors (64671).

2391421 is an equidigital number, since it uses as much as digits as its factorization.

2391421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64670.

The product of its digits is 432, while the sum is 22.

The square root of 2391421 is about 1546.4219993262. The cubic root of 2391421 is about 133.7268699630.

The spelling of 2391421 in words is "two million, three hundred ninety-one thousand, four hundred twenty-one".