74740821 has 4 divisors (see below), whose sum is σ = 99654432. Its totient is φ = 49827212.

The previous prime is 74740811. The next prime is 74740829. The reversal of 74740821 is 12804747.

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 74740821 - 2⁷ = 74740693 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74740829) 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 3 ways as a sum of consecutive naturals, for example, 12456801 + ... + 12456806.

It is an arithmetic number, because the mean of its divisors is an integer number (24913608).

Almost surely, 2^74740821 is an apocalyptic number.

It is an amenable number.

74740821 is a deficient number, since it is larger than the sum of its proper divisors (24913611).

74740821 is a wasteful number, since it uses less digits than its factorization.

74740821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24913610.

The product of its (nonzero) digits is 12544, while the sum is 33.

The square root of 74740821 is about 8645.2773813221. The cubic root of 74740821 is about 421.2299941483.

The spelling of 74740821 in words is "seventy-four million, seven hundred forty thousand, eight hundred twenty-one".