7129421 has 4 divisors (see below), whose sum is σ = 7677852. Its totient is φ = 6580992.

The previous prime is 7129417. The next prime is 7129439. The reversal of 7129421 is 1249217.

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 343396 + 6786025 = 586^2 + 2605^2 .

It is a cyclic number.

It is not a de Polignac number, because 7129421 - 2² = 7129417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7129481) 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, 274196 + ... + 274221.

It is an arithmetic number, because the mean of its divisors is an integer number (1919463).

Almost surely, 2^7129421 is an apocalyptic number.

It is an amenable number.

7129421 is a deficient number, since it is larger than the sum of its proper divisors (548431).

7129421 is a wasteful number, since it uses less digits than its factorization.

7129421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548430.

The product of its digits is 1008, while the sum is 26.

The square root of 7129421 is about 2670.0975637605. The cubic root of 7129421 is about 192.4648476882.

It can be divided in two parts, 71 and 29421, that added together give a palindrome (29492).

The spelling of 7129421 in words is "seven million, one hundred twenty-nine thousand, four hundred twenty-one".