641306961 has 12 divisors (see below), whose sum is σ = 934990992. Its totient is φ = 423541656.

The previous prime is 641306959. The next prime is 641306983. The reversal of 641306961 is 169603146.

641306961 is a `hidden beast` number, since 641 + 3 + 0 + 6 + 9 + 6 + 1 = 666.

It is not a de Polignac number, because 641306961 - 2¹ = 641306959 is a prime.

It is a super-2 number, since 2×641306961² = 822549236454111042, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (641306921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 332011 + ... + 333936.

It is an arithmetic number, because the mean of its divisors is an integer number (77915916).

Almost surely, 2^641306961 is an apocalyptic number.

It is an amenable number.

641306961 is a deficient number, since it is larger than the sum of its proper divisors (293684031).

641306961 is a wasteful number, since it uses less digits than its factorization.

641306961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666060 (or 666057 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 641306961 is about 25324.0391920404. The cubic root of 641306961 is about 862.3600942574.

The spelling of 641306961 in words is "six hundred forty-one million, three hundred six thousand, nine hundred sixty-one".