20106540 has 72 divisors (see below), whose sum is σ = 62658960. Its totient is φ = 5215104.

The previous prime is 20106521. The next prime is 20106589. The reversal of 20106540 is 4560102.

It is a happy number.

20106540 is a `hidden beast` number, since 2 + 0 + 10 + 654 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5151 + ... + 8169.

Almost surely, 2^20106540 is an apocalyptic number.

20106540 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 20106540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31329480).

20106540 is an abundant number, since it is smaller than the sum of its proper divisors (42552420).

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

20106540 is a wasteful number, since it uses less digits than its factorization.

20106540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3071 (or 3066 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20106540 is about 4484.0316680416. The cubic root of 20106540 is about 271.9228984178.

Adding to 20106540 its reverse (4560102), we get a palindrome (24666642).

The spelling of 20106540 in words is "twenty million, one hundred six thousand, five hundred forty".