20420380 has 12 divisors (see below), whose sum is σ = 42882840. Its totient is φ = 8168144.

The previous prime is 20420377. The next prime is 20420443. The reversal of 20420380 is 8302402.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 510490 + ... + 510529.

It is an arithmetic number, because the mean of its divisors is an integer number (3573570).

Almost surely, 2^20420380 is an apocalyptic number.

20420380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20420380 is an abundant number, since it is smaller than the sum of its proper divisors (22462460).

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

20420380 is a wasteful number, since it uses less digits than its factorization.

20420380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021028 (or 1021026 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 20420380 is about 4518.8914569837. The cubic root of 20420380 is about 273.3304018457.

Adding to 20420380 its reverse (8302402), we get a palindrome (28722782).

The spelling of 20420380 in words is "twenty million, four hundred twenty thousand, three hundred eighty".