641740509 has 16 divisors (see below), whose sum is σ = 951246400. Its totient is φ = 427593168.

The previous prime is 641740499. The next prime is 641740511. The reversal of 641740509 is 905047146.

641740509 is a `hidden beast` number, since 641 + 7 + 4 + 0 + 5 + 0 + 9 = 666.

It is not a de Polignac number, because 641740509 - 2⁴ = 641740493 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 (641740909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54087 + ... + 64875.

It is an arithmetic number, because the mean of its divisors is an integer number (59452900).

Almost surely, 2^641740509 is an apocalyptic number.

It is an amenable number.

641740509 is a deficient number, since it is larger than the sum of its proper divisors (309505891).

641740509 is a wasteful number, since it uses less digits than its factorization.

641740509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13001 (or 12995 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 641740509 is about 25332.5977546717. The cubic root of 641740509 is about 862.5543799362.

The spelling of 641740509 in words is "six hundred forty-one million, seven hundred forty thousand, five hundred nine".