647948077 has 4 divisors (see below), whose sum is σ = 740512096. Its totient is φ = 555384060.

The previous prime is 647948071. The next prime is 647948087. The reversal of 647948077 is 770849746.

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: 770849746 = 2 ⋅385424873.

It is not a de Polignac number, because 647948077 - 2¹⁹ = 647423789 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 (647948071) 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, 46281999 + ... + 46282012.

It is an arithmetic number, because the mean of its divisors is an integer number (185128024).

Almost surely, 2^647948077 is an apocalyptic number.

It is an amenable number.

647948077 is a deficient number, since it is larger than the sum of its proper divisors (92564019).

647948077 is an equidigital number, since it uses as much as digits as its factorization.

647948077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92564018.

The product of its (nonzero) digits is 2370816, while the sum is 52.

The square root of 647948077 is about 25454.8242382461. The cubic root of 647948077 is about 865.3266286274.

The spelling of 647948077 in words is "six hundred forty-seven million, nine hundred forty-eight thousand, seventy-seven".