647139653 has 4 divisors (see below), whose sum is σ = 656254368. Its totient is φ = 638024940.

The previous prime is 647139589. The next prime is 647139673. The reversal of 647139653 is 356931746.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 356931746 = 2 ⋅178465873.

It is a cyclic number.

It is not a de Polignac number, because 647139653 - 2⁶ = 647139589 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647139673) 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, 4557251 + ... + 4557392.

It is an arithmetic number, because the mean of its divisors is an integer number (164063592).

Almost surely, 2^647139653 is an apocalyptic number.

It is an amenable number.

647139653 is a deficient number, since it is larger than the sum of its proper divisors (9114715).

647139653 is an equidigital number, since it uses as much as digits as its factorization.

647139653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9114714.

The product of its digits is 408240, while the sum is 44.

The square root of 647139653 is about 25438.9396988161. The cubic root of 647139653 is about 864.9665987749.

The spelling of 647139653 in words is "six hundred forty-seven million, one hundred thirty-nine thousand, six hundred fifty-three".