647121473 has 8 divisors (see below), whose sum is σ = 688741128. Its totient is φ = 605896704.

The previous prime is 647121463. The next prime is 647121481. The reversal of 647121473 is 374121746.

It can be written as a sum of positive squares in 4 ways, for example, as 184742464 + 462379009 = 13592^2 + 21503^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 647121473 - 2¹⁴ = 647105089 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (647121463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95336 + ... + 101897.

It is an arithmetic number, because the mean of its divisors is an integer number (86092641).

Almost surely, 2^647121473 is an apocalyptic number.

It is an amenable number.

647121473 is a deficient number, since it is larger than the sum of its proper divisors (41619655).

647121473 is a wasteful number, since it uses less digits than its factorization.

647121473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197443.

The product of its digits is 28224, while the sum is 35.

The square root of 647121473 is about 25438.5823700929. The cubic root of 647121473 is about 864.9584989055.

The spelling of 647121473 in words is "six hundred forty-seven million, one hundred twenty-one thousand, four hundred seventy-three".