20323290 has 96 divisors (see below), whose sum is σ = 55577088. Its totient is φ = 4723200.

The previous prime is 20323271. The next prime is 20323291. The reversal of 20323290 is 9232302.

It is a super-2 number, since 2×20323290² = 826072232848200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20323291) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 495670 + ... + 495710.

It is an arithmetic number, because the mean of its divisors is an integer number (578928).

Almost surely, 2^20323290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20323290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27788544).

20323290 is an abundant number, since it is smaller than the sum of its proper divisors (35253798).

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

20323290 is a wasteful number, since it uses less digits than its factorization.

20323290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136 (or 95 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 21.

The square root of 20323290 is about 4508.1359784283. The cubic root of 20323290 is about 272.8965245383.

Adding to 20323290 its reverse (9232302), we get a palindrome (29555592).

The spelling of 20323290 in words is "twenty million, three hundred twenty-three thousand, two hundred ninety".