75299721 has 24 divisors (see below), whose sum is σ = 117675360. Its totient is φ = 42702912.

The previous prime is 75299701. The next prime is 75299737. The reversal of 75299721 is 12799257.

It is not a de Polignac number, because 75299721 - 2¹⁵ = 75266953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (75299701) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18270 + ... + 22008.

It is an arithmetic number, because the mean of its divisors is an integer number (4903140).

Almost surely, 2^75299721 is an apocalyptic number.

It is an amenable number.

75299721 is a deficient number, since it is larger than the sum of its proper divisors (42375639).

75299721 is a wasteful number, since it uses less digits than its factorization.

75299721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3893 (or 3886 counting only the distinct ones).

The product of its digits is 79380, while the sum is 42.

The square root of 75299721 is about 8677.5411839991. The cubic root of 75299721 is about 422.2773514990.

The spelling of 75299721 in words is "seventy-five million, two hundred ninety-nine thousand, seven hundred twenty-one".