20418309340 has 576 divisors, whose sum is σ = 60537093120. Its totient is φ = 5656780800.

The previous prime is 20418309319. The next prime is 20418309343. The reversal of 20418309340 is 4390381402.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a junction number, because it is equal to n+sod(n) for n = 20418309296 and 20418309305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20418309343) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 658655125 + ... + 658655155.

It is an arithmetic number, because the mean of its divisors is an integer number (105099120).

Almost surely, 2^20418309340 is an apocalyptic number.

20418309340 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 20418309340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30268546560).

20418309340 is an abundant number, since it is smaller than the sum of its proper divisors (40118783780).

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

20418309340 is a wasteful number, since it uses less digits than its factorization.

20418309340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The spelling of 20418309340 in words is "twenty billion, four hundred eighteen million, three hundred nine thousand, three hundred forty".