647577346621 has 4 divisors (see below), whose sum is σ = 647584342272. Its totient is φ = 647570350972.

The previous prime is 647577346601. The next prime is 647577346631. The reversal of 647577346621 is 126643775746.

It is a happy number.

647577346621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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: 126643775746 = 2 ⋅63321887873.

It is a cyclic number.

It is not a de Polignac number, because 647577346621 - 2⁹ = 647577346109 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647577346601) 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, 3357085 + ... + 3544738.

It is an arithmetic number, because the mean of its divisors is an integer number (161896085568).

Almost surely, 2^647577346621 is an apocalyptic number.

It is an amenable number.

647577346621 is a deficient number, since it is larger than the sum of its proper divisors (6995651).

647577346621 is an equidigital number, since it uses as much as digits as its factorization.

647577346621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6995650.

The product of its digits is 35562240, while the sum is 58.

The spelling of 647577346621 in words is "six hundred forty-seven billion, five hundred seventy-seven million, three hundred forty-six thousand, six hundred twenty-one".