6640501405 has 8 divisors (see below), whose sum is σ = 7969524192. Its totient is φ = 5311786128.

The previous prime is 6640501397. The next prime is 6640501433. The reversal of 6640501405 is 5041050466.

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 6640501405 - 2³ = 6640501397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26347 + ... + 118216.

It is an arithmetic number, because the mean of its divisors is an integer number (996190524).

Almost surely, 2^6640501405 is an apocalyptic number.

It is an amenable number.

6640501405 is a deficient number, since it is larger than the sum of its proper divisors (1329022787).

6640501405 is a wasteful number, since it uses less digits than its factorization.

6640501405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153755.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 6640501405 is about 81489.2717172021. The cubic root of 6640501405 is about 1879.6065840618.

The spelling of 6640501405 in words is "six billion, six hundred forty million, five hundred one thousand, four hundred five".