7123540 has 24 divisors (see below), whose sum is σ = 15016680. Its totient is φ = 2838528.

The previous prime is 7123513. The next prime is 7123547. The reversal of 7123540 is 453217.

It can be written as a sum of positive squares in 4 ways, for example, as 217156 + 6906384 = 466^2 + 2628^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7123547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6556 + ... + 7564.

It is an arithmetic number, because the mean of its divisors is an integer number (625695).

Almost surely, 2^7123540 is an apocalyptic number.

It is an amenable number.

7123540 is an abundant number, since it is smaller than the sum of its proper divisors (7893140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7123540 is a wasteful number, since it uses less digits than its factorization.

7123540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1371 (or 1369 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 7123540 is about 2668.9960659394. The cubic root of 7123540 is about 192.4119122469.

Adding to 7123540 its reverse (453217), we get a palindrome (7576757).

The spelling of 7123540 in words is "seven million, one hundred twenty-three thousand, five hundred forty".