74643509 has 2 divisors, whose sum is σ = 74643510. Its totient is φ = 74643508.

The previous prime is 74643469. The next prime is 74643511. The reversal of 74643509 is 90534647.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70140625 + 4502884 = 8375^2 + 2122^2 .

It is a cyclic number.

It is not a de Polignac number, because 74643509 - 2²⁰ = 73594933 is a prime.

Together with 74643511, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (74643559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37321754 + 37321755.

It is an arithmetic number, because the mean of its divisors is an integer number (37321755).

Almost surely, 2^74643509 is an apocalyptic number.

It is an amenable number.

74643509 is a deficient number, since it is larger than the sum of its proper divisors (1).

74643509 is an equidigital number, since it uses as much as digits as its factorization.

74643509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 74643509 is about 8639.6475043835. The cubic root of 74643509 is about 421.0471019644.

The spelling of 74643509 in words is "seventy-four million, six hundred forty-three thousand, five hundred nine".