7253821 has 4 divisors (see below), whose sum is σ = 7269952. Its totient is φ = 7237692.

The previous prime is 7253819. The next prime is 7253833. The reversal of 7253821 is 1283527.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1283527 = 7 ⋅183361.

It is a cyclic number.

It is not a de Polignac number, because 7253821 - 2¹ = 7253819 is a prime.

It is a Duffinian number.

7253821 is a lucky number.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 7253821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7253861) 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, 7371 + ... + 8296.

It is an arithmetic number, because the mean of its divisors is an integer number (1817488).

Almost surely, 2^7253821 is an apocalyptic number.

It is an amenable number.

7253821 is a deficient number, since it is larger than the sum of its proper divisors (16131).

7253821 is a wasteful number, since it uses less digits than its factorization.

7253821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16130.

The product of its digits is 3360, while the sum is 28.

The square root of 7253821 is about 2693.2918519908. The cubic root of 7253821 is about 193.5778274843.

It can be divided in two parts, 7 and 253821, that added together give a triangular number (253828 = T₇₁₂).

The spelling of 7253821 in words is "seven million, two hundred fifty-three thousand, eight hundred twenty-one".