74581286921 has 4 divisors (see below), whose sum is σ = 74582008644. Its totient is φ = 74580565200.

The previous prime is 74581286903. The next prime is 74581286933. The reversal of 74581286921 is 12968218547.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12968218547 = 23 ⋅563835589.

It can be written as a sum of positive squares in 2 ways, for example, as 3527053321 + 71054233600 = 59389^2 + 266560^2 .

It is a cyclic number.

It is not a de Polignac number, because 74581286921 - 2¹⁰ = 74581285897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (74581286951) 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, 173390 + ... + 423351.

It is an arithmetic number, because the mean of its divisors is an integer number (18645502161).

Almost surely, 2^74581286921 is an apocalyptic number.

It is an amenable number.

74581286921 is a deficient number, since it is larger than the sum of its proper divisors (721723).

74581286921 is a wasteful number, since it uses less digits than its factorization.

74581286921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 721722.

The product of its digits is 1935360, while the sum is 53.

The spelling of 74581286921 in words is "seventy-four billion, five hundred eighty-one million, two hundred eighty-six thousand, nine hundred twenty-one".