636057661 has 8 divisors (see below), whose sum is σ = 669962880. Its totient is φ = 602195328.

The previous prime is 636057637. The next prime is 636057671. The reversal of 636057661 is 166750636.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-636057661 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 (636057671) 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, 22380 + ... + 42106.

It is an arithmetic number, because the mean of its divisors is an integer number (83745360).

Almost surely, 2^636057661 is an apocalyptic number.

It is an amenable number.

636057661 is a deficient number, since it is larger than the sum of its proper divisors (33905219).

636057661 is a wasteful number, since it uses less digits than its factorization.

636057661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21443.

The product of its (nonzero) digits is 136080, while the sum is 40.

The square root of 636057661 is about 25220.1836036140. The cubic root of 636057661 is about 860.0007486022. Note that the first 3 decimals are identical.

The spelling of 636057661 in words is "six hundred thirty-six million, fifty-seven thousand, six hundred sixty-one".