74557991 has 4 divisors (see below), whose sum is σ = 74720184. Its totient is φ = 74395800.

The previous prime is 74557963. The next prime is 74558009. The reversal of 74557991 is 19975547.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 74557991 - 2¹⁰ = 74556967 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 (74557391) 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, 80405 + ... + 81326.

It is an arithmetic number, because the mean of its divisors is an integer number (18680046).

Almost surely, 2^74557991 is an apocalyptic number.

74557991 is a deficient number, since it is larger than the sum of its proper divisors (162193).

74557991 is a wasteful number, since it uses less digits than its factorization.

74557991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162192.

The product of its digits is 396900, while the sum is 47.

The square root of 74557991 is about 8634.6969257757. The cubic root of 74557991 is about 420.8862446385.

The spelling of 74557991 in words is "seventy-four million, five hundred fifty-seven thousand, nine hundred ninety-one".