7143921 has 6 divisors (see below), whose sum is σ = 10319010. Its totient is φ = 4762608.

The previous prime is 7143911. The next prime is 7143931. The reversal of 7143921 is 1293417.

It is an interprime number because it is at equal distance from previous prime (7143911) and next prime (7143931).

It can be written as a sum of positive squares in only one way, i.e., 5239521 + 1904400 = 2289^2 + 1380^2 .

It is not a de Polignac number, because 7143921 - 2¹⁷ = 7012849 is a prime.

It is a Curzon number.

7143921 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (7143911) 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 5 ways as a sum of consecutive naturals, for example, 396876 + ... + 396893.

It is an arithmetic number, because the mean of its divisors is an integer number (1719835).

Almost surely, 2^7143921 is an apocalyptic number.

It is an amenable number.

7143921 is a deficient number, since it is larger than the sum of its proper divisors (3175089).

7143921 is a wasteful number, since it uses less digits than its factorization.

7143921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 793775 (or 793772 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 7143921 is about 2672.8114411608. The cubic root of 7143921 is about 192.5952393178.

The spelling of 7143921 in words is "seven million, one hundred forty-three thousand, nine hundred twenty-one".