646020761 has 4 divisors (see below), whose sum is σ = 646473012. Its totient is φ = 645568512.

The previous prime is 646020743. The next prime is 646020779. The reversal of 646020761 is 167020646.

646020761 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.

It is an interprime number because it is at equal distance from previous prime (646020743) and next prime (646020779).

It can be written as a sum of positive squares in 2 ways, for example, as 606883225 + 39137536 = 24635^2 + 6256^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646020761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646020701) 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, 223976 + ... + 226841.

It is an arithmetic number, because the mean of its divisors is an integer number (161618253).

Almost surely, 2^646020761 is an apocalyptic number.

It is an amenable number.

646020761 is a deficient number, since it is larger than the sum of its proper divisors (452251).

646020761 is a wasteful number, since it uses less digits than its factorization.

646020761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452250.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 646020761 is about 25416.9384663063. The cubic root of 646020761 is about 864.4678076658.

The spelling of 646020761 in words is "six hundred forty-six million, twenty thousand, seven hundred sixty-one".