7428493921 has 4 divisors (see below), whose sum is σ = 7429864644. Its totient is φ = 7427123200.

The previous prime is 7428493907. The next prime is 7428493937. The reversal of 7428493921 is 1293948247.

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 2046657600 + 5381836321 = 45240^2 + 73361^2 .

It is a cyclic number.

It is not a de Polignac number, because 7428493921 - 2⁵ = 7428493889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7428493981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 677200 + ... + 688081.

It is an arithmetic number, because the mean of its divisors is an integer number (1857466161).

Almost surely, 2^7428493921 is an apocalyptic number.

It is an amenable number.

7428493921 is a deficient number, since it is larger than the sum of its proper divisors (1370723).

7428493921 is a wasteful number, since it uses less digits than its factorization.

7428493921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1370722.

The product of its digits is 870912, while the sum is 49.

The square root of 7428493921 is about 86188.7110995402. The cubic root of 7428493921 is about 1951.1931265858.

The spelling of 7428493921 in words is "seven billion, four hundred twenty-eight million, four hundred ninety-three thousand, nine hundred twenty-one".