20420604 has 72 divisors (see below), whose sum is σ = 55652688. Its totient is φ = 6289920.

The previous prime is 20420591. The next prime is 20420627. The reversal of 20420604 is 40602402.

20420604 = 318² + 319² + ... + 453².

20420604 is a `hidden beast` number, since 20 + 42 + 0 + 604 = 666.

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

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 37059 + ... + 37605.

It is an arithmetic number, because the mean of its divisors is an integer number (772954).

Almost surely, 2^20420604 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 20420604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27826344).

20420604 is an abundant number, since it is smaller than the sum of its proper divisors (35232084).

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

20420604 is a wasteful number, since it uses less digits than its factorization.

20420604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635 (or 630 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 20420604 is about 4518.9162417553. The cubic root of 20420604 is about 273.3314012686.

The spelling of 20420604 in words is "twenty million, four hundred twenty thousand, six hundred four".