631206561 has 8 divisors (see below), whose sum is σ = 843367680. Its totient is φ = 419924912.

The previous prime is 631206559. The next prime is 631206599. The reversal of 631206561 is 165602136.

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 631206561 - 2¹ = 631206559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (631206551) 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, 218190 + ... + 221063.

It is an arithmetic number, because the mean of its divisors is an integer number (105420960).

Almost surely, 2^631206561 is an apocalyptic number.

It is an amenable number.

631206561 is a deficient number, since it is larger than the sum of its proper divisors (212161119).

631206561 is a wasteful number, since it uses less digits than its factorization.

631206561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439735.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 631206561 is about 25123.8245695197. The cubic root of 631206561 is about 857.8088084161.

Adding to 631206561 its reverse (165602136), we get a palindrome (796808697).

The spelling of 631206561 in words is "six hundred thirty-one million, two hundred six thousand, five hundred sixty-one".