20190390 has 128 divisors (see below), whose sum is σ = 57853440. Its totient is φ = 4454400.

The previous prime is 20190371. The next prime is 20190421. The reversal of 20190390 is 9309102.

20190390 = T₂₉₀ + T₂₉₁ + ... + T₅₂₅.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20190390.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 330960 + ... + 331020.

It is an arithmetic number, because the mean of its divisors is an integer number (451980).

Almost surely, 2^20190390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20190390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28926720).

20190390 is an abundant number, since it is smaller than the sum of its proper divisors (37663050).

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

20190390 is a wasteful number, since it uses less digits than its factorization.

20190390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158.

The product of its (nonzero) digits is 486, while the sum is 24.

The square root of 20190390 is about 4493.3717851965. The cubic root of 20190390 is about 272.3003728295.

Adding to 20190390 its reverse (9309102), we get a palindrome (29499492).

The spelling of 20190390 in words is "twenty million, one hundred ninety thousand, three hundred ninety".