42721730243 has 4 divisors (see below), whose sum is σ = 42724324608. Its totient is φ = 42719135880.

The previous prime is 42721730237. The next prime is 42721730297. The reversal of 42721730243 is 34203712724.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42721730243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42720730243) 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, 1272323 + ... + 1305468.

It is an arithmetic number, because the mean of its divisors is an integer number (10681081152).

Almost surely, 2^42721730243 is an apocalyptic number.

42721730243 is a deficient number, since it is larger than the sum of its proper divisors (2594365).

42721730243 is a wasteful number, since it uses less digits than its factorization.

42721730243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2594364.

The product of its (nonzero) digits is 56448, while the sum is 35.

The spelling of 42721730243 in words is "forty-two billion, seven hundred twenty-one million, seven hundred thirty thousand, two hundred forty-three".