64739905 has 8 divisors (see below), whose sum is σ = 77759784. Its totient is φ = 51744000.

The previous prime is 64739881. The next prime is 64739921. The reversal of 64739905 is 50993746.

It can be written as a sum of positive squares in 4 ways, for example, as 1648656 + 63091249 = 1284^2 + 7943^2 .

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

It is not a de Polignac number, because 64739905 - 2¹⁹ = 64215617 is a prime.

It is a Duffinian 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, 615 + ... + 11395.

It is an arithmetic number, because the mean of its divisors is an integer number (9719973).

Almost surely, 2^64739905 is an apocalyptic number.

It is an amenable number.

64739905 is a deficient number, since it is larger than the sum of its proper divisors (13019879).

64739905 is a wasteful number, since it uses less digits than its factorization.

64739905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11987.

The product of its (nonzero) digits is 204120, while the sum is 43.

The square root of 64739905 is about 8046.1111724857. Note that the first 4 decimals coincide. The cubic root of 64739905 is about 401.5355662970.

The spelling of 64739905 in words is "sixty-four million, seven hundred thirty-nine thousand, nine hundred five".