7251421 has 4 divisors (see below), whose sum is σ = 7501500. Its totient is φ = 7001344.

The previous prime is 7251397. The next prime is 7251481. The reversal of 7251421 is 1241527.

It is a happy number.

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 6180196 + 1071225 = 2486^2 + 1035^2 .

It is a cyclic number.

It is not a de Polignac number, because 7251421 - 2⁵ = 7251389 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7251392 and 7251401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7251481) 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, 124996 + ... + 125053.

It is an arithmetic number, because the mean of its divisors is an integer number (1875375).

Almost surely, 2^7251421 is an apocalyptic number.

It is an amenable number.

7251421 is a deficient number, since it is larger than the sum of its proper divisors (250079).

7251421 is a wasteful number, since it uses less digits than its factorization.

7251421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250078.

The product of its digits is 560, while the sum is 22.

The square root of 7251421 is about 2692.8462637143. The cubic root of 7251421 is about 193.5564760690.

Adding to 7251421 its reverse (1241527), we get a palindrome (8492948).

It can be divided in two parts, 725 and 1421, that multiplied together give a square (1030225 = 1015²).

The spelling of 7251421 in words is "seven million, two hundred fifty-one thousand, four hundred twenty-one".