20331390 has 32 divisors (see below), whose sum is σ = 48944160. Its totient is φ = 5405184.

The previous prime is 20331373. The next prime is 20331403. The reversal of 20331390 is 9313302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11442 + ... + 13098.

It is an arithmetic number, because the mean of its divisors is an integer number (1529505).

Almost surely, 2^20331390 is an apocalyptic number.

20331390 is an abundant number, since it is smaller than the sum of its proper divisors (28612770).

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

20331390 is a wasteful number, since it uses less digits than its factorization.

20331390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2076.

The product of its (nonzero) digits is 486, while the sum is 21.

The square root of 20331390 is about 4509.0342646735. The cubic root of 20331390 is about 272.9327747098.

Adding to 20331390 its reverse (9313302), we get a palindrome (29644692).

The spelling of 20331390 in words is "twenty million, three hundred thirty-one thousand, three hundred ninety".