74991609 has 48 divisors (see below), whose sum is σ = 141013440. Its totient is φ = 38949120.

The previous prime is 74991577. The next prime is 74991611. The reversal of 74991609 is 90619947.

74991609 = 70² + 71² + ... + 608².

It is not a de Polignac number, because 74991609 - 2⁵ = 74991577 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (74993609) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11977 + ... + 17129.

It is an arithmetic number, because the mean of its divisors is an integer number (2937780).

Almost surely, 2^74991609 is an apocalyptic number.

It is an amenable number.

74991609 is a deficient number, since it is larger than the sum of its proper divisors (66021831).

74991609 is a wasteful number, since it uses less digits than its factorization.

74991609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5187 (or 5174 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 74991609 is about 8659.7695696826. The cubic root of 74991609 is about 421.7006048566.

The spelling of 74991609 in words is "seventy-four million, nine hundred ninety-one thousand, six hundred nine".