74126821 has 4 divisors (see below), whose sum is σ = 74144044. Its totient is φ = 74109600.

The previous prime is 74126803. The next prime is 74126827. The reversal of 74126821 is 12862147.

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: 12862147 = 71 ⋅181157.

It can be written as a sum of positive squares in 2 ways, for example, as 32330596 + 41796225 = 5686^2 + 6465^2 .

It is a cyclic number.

It is not a de Polignac number, because 74126821 - 2¹¹ = 74124773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74126827) 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, 4081 + ... + 12841.

It is an arithmetic number, because the mean of its divisors is an integer number (18536011).

Almost surely, 2^74126821 is an apocalyptic number.

It is an amenable number.

74126821 is a deficient number, since it is larger than the sum of its proper divisors (17223).

74126821 is an equidigital number, since it uses as much as digits as its factorization.

74126821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17222.

The product of its digits is 5376, while the sum is 31.

The square root of 74126821 is about 8609.6934324051. The cubic root of 74126821 is about 420.0733450896.

Adding to 74126821 its reverse (12862147), we get a palindrome (86988968).

It can be divided in two parts, 74126 and 821, that added together give a palindrome (74947).

The spelling of 74126821 in words is "seventy-four million, one hundred twenty-six thousand, eight hundred twenty-one".