646982653 has 8 divisors (see below), whose sum is σ = 658156536. Its totient is φ = 635827200.

The previous prime is 646982647. The next prime is 646982657. The reversal of 646982653 is 356289646.

It can be written as a sum of positive squares in 4 ways, for example, as 31843449 + 615139204 = 5643^2 + 24802^2 .

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 646982653 - 2⁵ = 646982621 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646982597 and 646982606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646982657) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79125 + ... + 86917.

It is an arithmetic number, because the mean of its divisors is an integer number (82269567).

Almost surely, 2^646982653 is an apocalyptic number.

It is an amenable number.

646982653 is a deficient number, since it is larger than the sum of its proper divisors (11173883).

646982653 is a wasteful number, since it uses less digits than its factorization.

646982653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9215.

The product of its digits is 1866240, while the sum is 49.

The square root of 646982653 is about 25435.8536911974. The cubic root of 646982653 is about 864.8966444052.

The spelling of 646982653 in words is "six hundred forty-six million, nine hundred eighty-two thousand, six hundred fifty-three".