20090340 has 72 divisors (see below), whose sum is σ = 61326720. Its totient is φ = 5323584.

The previous prime is 20090333. The next prime is 20090341. The reversal of 20090340 is 4309002.

It is a super-2 number, since 2×20090340² = 807243522631200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (20090341) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 42787 + ... + 43253.

It is an arithmetic number, because the mean of its divisors is an integer number (851760).

Almost surely, 2^20090340 is an apocalyptic number.

20090340 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 20090340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30663360).

20090340 is an abundant number, since it is smaller than the sum of its proper divisors (41236380).

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

20090340 is a wasteful number, since it uses less digits than its factorization.

20090340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721 (or 716 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 20090340 is about 4482.2248939561. The cubic root of 20090340 is about 271.8498486444.

Adding to 20090340 its reverse (4309002), we get a palindrome (24399342).

The spelling of 20090340 in words is "twenty million, ninety thousand, three hundred forty".