7405021 has 4 divisors (see below), whose sum is σ = 7974652. Its totient is φ = 6835392.

The previous prime is 7405009. The next prime is 7405049. The reversal of 7405021 is 1205047.

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 1999396 + 5405625 = 1414^2 + 2325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7405021 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7405021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7405061) 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, 284796 + ... + 284821.

It is an arithmetic number, because the mean of its divisors is an integer number (1993663).

Almost surely, 2^7405021 is an apocalyptic number.

It is an amenable number.

7405021 is a deficient number, since it is larger than the sum of its proper divisors (569631).

7405021 is a wasteful number, since it uses less digits than its factorization.

7405021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569630.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 7405021 is about 2721.2168234082. The cubic root of 7405021 is about 194.9135799397.

The spelling of 7405021 in words is "seven million, four hundred five thousand, twenty-one".