75008721 has 16 divisors (see below), whose sum is σ = 102936960. Its totient is φ = 48554880.

The previous prime is 75008701. The next prime is 75008771. The reversal of 75008721 is 12780057.

It is a happy number.

It is not a de Polignac number, because 75008721 - 2¹⁰ = 75007697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (75008701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26836 + ... + 29498.

It is an arithmetic number, because the mean of its divisors is an integer number (6433560).

Almost surely, 2^75008721 is an apocalyptic number.

It is an amenable number.

75008721 is a deficient number, since it is larger than the sum of its proper divisors (27928239).

75008721 is a wasteful number, since it uses less digits than its factorization.

75008721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2936.

The product of its (nonzero) digits is 3920, while the sum is 30.

The square root of 75008721 is about 8660.7575303780. The cubic root of 75008721 is about 421.7326777424.

Adding to 75008721 its reverse (12780057), we get a palindrome (87788778).

The spelling of 75008721 in words is "seventy-five million, eight thousand, seven hundred twenty-one".