20390142 has 8 divisors (see below), whose sum is σ = 40780296. Its totient is φ = 6796712.

The previous prime is 20390129. The next prime is 20390147. The reversal of 20390142 is 24109302.

It is a sphenic number, since it is the product of 3 distinct primes.

20390142 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20390147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1699173 + ... + 1699184.

It is an arithmetic number, because the mean of its divisors is an integer number (5097537).

Almost surely, 2^20390142 is an apocalyptic number.

20390142 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20390142 is a wasteful number, since it uses less digits than its factorization.

20390142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3398362.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 20390142 is about 4515.5444854414. The cubic root of 20390142 is about 273.1954215374.

Adding to 20390142 its reverse (24109302), we get a palindrome (44499444).

The spelling of 20390142 in words is "twenty million, three hundred ninety thousand, one hundred forty-two".