20136461 has 4 divisors (see below), whose sum is σ = 20157024. Its totient is φ = 20115900.

The previous prime is 20136443. The next prime is 20136463. The reversal of 20136461 is 16463102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20136461 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 (20136463) 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, 8735 + ... + 10796.

It is an arithmetic number, because the mean of its divisors is an integer number (5039256).

Almost surely, 2^20136461 is an apocalyptic number.

It is an amenable number.

20136461 is a deficient number, since it is larger than the sum of its proper divisors (20563).

20136461 is a wasteful number, since it uses less digits than its factorization.

20136461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20562.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 20136461 is about 4487.3668225364. The cubic root of 20136461 is about 272.0577164502.

Adding to 20136461 its reverse (16463102), we get a palindrome (36599563).

The spelling of 20136461 in words is "twenty million, one hundred thirty-six thousand, four hundred sixty-one".