74973991 has 4 divisors (see below), whose sum is σ = 74991312. Its totient is φ = 74956672.

The previous prime is 74973989. The next prime is 74974007. The reversal of 74973991 is 19937947.

It is a happy number.

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: 19937947 = 2621 ⋅7607.

It is a cyclic number.

It is not a de Polignac number, because 74973991 - 2¹ = 74973989 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 (74973911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4110 + ... + 12916.

It is an arithmetic number, because the mean of its divisors is an integer number (18747828).

Almost surely, 2^74973991 is an apocalyptic number.

74973991 is a deficient number, since it is larger than the sum of its proper divisors (17321).

74973991 is an equidigital number, since it uses as much as digits as its factorization.

74973991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17320.

The product of its digits is 428652, while the sum is 49.

The square root of 74973991 is about 8658.7522773203. The cubic root of 74973991 is about 421.6675784809.

The spelling of 74973991 in words is "seventy-four million, nine hundred seventy-three thousand, nine hundred ninety-one".