20061540 has 96 divisors (see below), whose sum is σ = 63221760. Its totient is φ = 5280768.

The previous prime is 20061539. The next prime is 20061553. The reversal of 20061540 is 4516002.

It is a happy number.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 52189 + ... + 52571.

It is an arithmetic number, because the mean of its divisors is an integer number (658560).

Almost surely, 2^20061540 is an apocalyptic number.

20061540 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 20061540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31610880).

20061540 is an abundant number, since it is smaller than the sum of its proper divisors (43160220).

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

20061540 is a wasteful number, since it uses less digits than its factorization.

20061540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498 (or 490 counting only the distinct ones).

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

The square root of 20061540 is about 4479.0110515604. The cubic root of 20061540 is about 271.7198853589.

Adding to 20061540 its reverse (4516002), we get a palindrome (24577542).

The spelling of 20061540 in words is "twenty million, sixty-one thousand, five hundred forty".