20420136 has 192 divisors, whose sum is σ = 67392000. Its totient is φ = 5512320.

The previous prime is 20420129. The next prime is 20420167. The reversal of 20420136 is 63102402.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 346075 + ... + 346133.

It is an arithmetic number, because the mean of its divisors is an integer number (351000).

Almost surely, 2^20420136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20420136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33696000).

20420136 is an abundant number, since it is smaller than the sum of its proper divisors (46971864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20420136 is a wasteful number, since it uses less digits than its factorization.

20420136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 20420136 is about 4518.8644591313. The cubic root of 20420136 is about 273.3293131803.

Adding to 20420136 its reverse (63102402), we get a palindrome (83522538).

The spelling of 20420136 in words is "twenty million, four hundred twenty thousand, one hundred thirty-six".