7724421 has 6 divisors (see below), whose sum is σ = 11157510. Its totient is φ = 5149608.

The previous prime is 7724419. The next prime is 7724447. The reversal of 7724421 is 1244277.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 6320196 + 1404225 = 2514^2 + 1185^2 .

It is not a de Polignac number, because 7724421 - 2¹ = 7724419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7724461) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 429126 + ... + 429143.

It is an arithmetic number, because the mean of its divisors is an integer number (1859585).

Almost surely, 2^7724421 is an apocalyptic number.

It is an amenable number.

7724421 is a deficient number, since it is larger than the sum of its proper divisors (3433089).

7724421 is a wasteful number, since it uses less digits than its factorization.

7724421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 858275 (or 858272 counting only the distinct ones).

The product of its digits is 3136, while the sum is 27.

The square root of 7724421 is about 2779.2842603807. The cubic root of 7724421 is about 197.6766224316.

Adding to 7724421 its reverse (1244277), we get a palindrome (8968698).

The spelling of 7724421 in words is "seven million, seven hundred twenty-four thousand, four hundred twenty-one".