20136661 has 8 divisors (see below), whose sum is σ = 21409920. Its totient is φ = 18896592.

The previous prime is 20136659. The next prime is 20136679. The reversal of 20136661 is 16663102.

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 20136661 - 2¹ = 20136659 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 (20136601) 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, 7041 + ... + 9478.

It is an arithmetic number, because the mean of its divisors is an integer number (2676240).

Almost surely, 2^20136661 is an apocalyptic number.

It is an amenable number.

20136661 is a deficient number, since it is larger than the sum of its proper divisors (1273259).

20136661 is a wasteful number, since it uses less digits than its factorization.

20136661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16595.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 20136661 is about 4487.3891072649. The cubic root of 20136661 is about 272.0586171607.

Adding to 20136661 its reverse (16663102), we get a palindrome (36799763).

The spelling of 20136661 in words is "twenty million, one hundred thirty-six thousand, six hundred sixty-one".