75316821 has 4 divisors (see below), whose sum is σ = 100422432. Its totient is φ = 50211212.

The previous prime is 75316781. The next prime is 75316831. The reversal of 75316821 is 12861357.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 75316821 - 2⁶ = 75316757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75316831) 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, 12552801 + ... + 12552806.

It is an arithmetic number, because the mean of its divisors is an integer number (25105608).

Almost surely, 2^75316821 is an apocalyptic number.

It is an amenable number.

75316821 is a deficient number, since it is larger than the sum of its proper divisors (25105611).

75316821 is a wasteful number, since it uses less digits than its factorization.

75316821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25105610.

The product of its digits is 10080, while the sum is 33.

The square root of 75316821 is about 8678.5264302184. The cubic root of 75316821 is about 422.3093144159.

The spelling of 75316821 in words is "seventy-five million, three hundred sixteen thousand, eight hundred twenty-one".