74193991 has 12 divisors (see below), whose sum is σ = 77786152. Its totient is φ = 70700256.

The previous prime is 74193989. The next prime is 74193997. The reversal of 74193991 is 19939147.

It is a happy number.

It is not a de Polignac number, because 74193991 - 2¹ = 74193989 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 (74193997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 428781 + ... + 428953.

Almost surely, 2^74193991 is an apocalyptic number.

74193991 is a deficient number, since it is larger than the sum of its proper divisors (3592161).

74193991 is an equidigital number, since it uses as much as digits as its factorization.

74193991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450 (or 277 counting only the distinct ones).

The product of its digits is 61236, while the sum is 43.

The square root of 74193991 is about 8613.5933848772. The cubic root of 74193991 is about 420.2001899022.

The spelling of 74193991 in words is "seventy-four million, one hundred ninety-three thousand, nine hundred ninety-one".