647623021 has 8 divisors (see below), whose sum is σ = 664663104. Its totient is φ = 630803040.

The previous prime is 647622977. The next prime is 647623027. The reversal of 647623021 is 120326746.

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 647623021 - 2¹⁹ = 647098733 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 (647623027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49056 + ... + 60841.

It is an arithmetic number, because the mean of its divisors is an integer number (83082888).

Almost surely, 2^647623021 is an apocalyptic number.

It is an amenable number.

647623021 is a deficient number, since it is larger than the sum of its proper divisors (17040083).

647623021 is a wasteful number, since it uses less digits than its factorization.

647623021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110051.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 647623021 is about 25448.4384786179. The cubic root of 647623021 is about 865.1819016695.

Adding to 647623021 its reverse (120326746), we get a palindrome (767949767).

The spelling of 647623021 in words is "six hundred forty-seven million, six hundred twenty-three thousand, twenty-one".