7921742 has 4 divisors (see below), whose sum is σ = 11882616. Its totient is φ = 3960870.

The previous prime is 7921723. The next prime is 7921757. The reversal of 7921742 is 2471297.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2471297 = 71 ⋅34807.

It is a junction number, because it is equal to n+sod(n) for n = 7921699 and 7921708.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 1980434 + ... + 1980437.

It is an arithmetic number, because the mean of its divisors is an integer number (2970654).

Almost surely, 2^7921742 is an apocalyptic number.

7921742 is a deficient number, since it is larger than the sum of its proper divisors (3960874).

7921742 is a wasteful number, since it uses less digits than its factorization.

7921742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3960873.

The product of its digits is 7056, while the sum is 32.

The square root of 7921742 is about 2814.5589352508. The cubic root of 7921742 is about 199.3457118693.

The spelling of 7921742 in words is "seven million, nine hundred twenty-one thousand, seven hundred forty-two".