20390000 has 50 divisors (see below), whose sum is σ = 49390440. Its totient is φ = 8152000.

The previous prime is 20389991. The next prime is 20390003. The reversal of 20390000 is 9302.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (50).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20390003) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 8981 + ... + 11019.

Almost surely, 2^20390000 is an apocalyptic number.

20390000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20390000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24695220).

20390000 is an abundant number, since it is smaller than the sum of its proper divisors (29000440).

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

20390000 is an equidigital number, since it uses as much as digits as its factorization.

20390000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2067 (or 2046 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 20390000 is about 4515.5287619503. The cubic root of 20390000 is about 273.1947873446.

Adding to 20390000 its reverse (9302), we get a palindrome (20399302).

The spelling of 20390000 in words is "twenty million, three hundred ninety thousand".