1640509609 has 8 divisors (see below), whose sum is σ = 1736396480. Its totient is φ = 1545577200.

The previous prime is 1640509601. The next prime is 1640509621. The reversal of 1640509609 is 9069050461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1640509609 - 2³ = 1640509601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1640509601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 235077 + ... + 241954.

It is an arithmetic number, because the mean of its divisors is an integer number (217049560).

Almost surely, 2^1640509609 is an apocalyptic number.

1640509609 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1640509609 is a deficient number, since it is larger than the sum of its proper divisors (95886871).

1640509609 is a wasteful number, since it uses less digits than its factorization.

1640509609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 477231.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 1640509609 is about 40503.2049225737. The cubic root of 1640509609 is about 1179.3958434124.

The spelling of 1640509609 in words is "one billion, six hundred forty million, five hundred nine thousand, six hundred nine".