75791721 has 8 divisors (see below), whose sum is σ = 101338560. Its totient is φ = 50386352.

The previous prime is 75791717. The next prime is 75791743. The reversal of 75791721 is 12719757.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 75791721 - 2² = 75791717 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 75791721.

It is not an unprimeable number, because it can be changed into a prime (75791701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34110 + ... + 36263.

It is an arithmetic number, because the mean of its divisors is an integer number (12667320).

Almost surely, 2^75791721 is an apocalyptic number.

It is an amenable number.

75791721 is a deficient number, since it is larger than the sum of its proper divisors (25546839).

75791721 is a wasteful number, since it uses less digits than its factorization.

75791721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70735.

The product of its digits is 30870, while the sum is 39.

The square root of 75791721 is about 8705.8440716567. The cubic root of 75791721 is about 423.1950600687.

The spelling of 75791721 in words is "seventy-five million, seven hundred ninety-one thousand, seven hundred twenty-one".