647438479 has 4 divisors (see below), whose sum is σ = 647816400. Its totient is φ = 647060560.

The previous prime is 647438453. The next prime is 647438497. The reversal of 647438479 is 974834746.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 974834746 = 2 ⋅487417373.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647438479 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 (647438579) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 186379 + ... + 189820.

It is an arithmetic number, because the mean of its divisors is an integer number (161954100).

Almost surely, 2^647438479 is an apocalyptic number.

647438479 is a deficient number, since it is larger than the sum of its proper divisors (377921).

647438479 is a wasteful number, since it uses less digits than its factorization.

647438479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377920.

The product of its digits is 4064256, while the sum is 52.

The square root of 647438479 is about 25444.8124182514. The cubic root of 647438479 is about 865.0997151911.

The spelling of 647438479 in words is "six hundred forty-seven million, four hundred thirty-eight thousand, four hundred seventy-nine".