74271821 has 4 divisors (see below), whose sum is σ = 79985052. Its totient is φ = 68558592.

The previous prime is 74271811. The next prime is 74271823. The reversal of 74271821 is 12817247.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12817247 = 1621 ⋅7907.

It can be written as a sum of positive squares in 2 ways, for example, as 13213225 + 61058596 = 3635^2 + 7814^2 .

It is a cyclic number.

It is not a de Polignac number, because 74271821 - 2¹⁴ = 74255437 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74271823) 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, 2856596 + ... + 2856621.

It is an arithmetic number, because the mean of its divisors is an integer number (19996263).

Almost surely, 2^74271821 is an apocalyptic number.

It is an amenable number.

74271821 is a deficient number, since it is larger than the sum of its proper divisors (5713231).

74271821 is a wasteful number, since it uses less digits than its factorization.

74271821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5713230.

The product of its digits is 6272, while the sum is 32.

The square root of 74271821 is about 8618.1100596360. The cubic root of 74271821 is about 420.3470695050.

The spelling of 74271821 in words is "seventy-four million, two hundred seventy-one thousand, eight hundred twenty-one".