20407140 has 288 divisors, whose sum is σ = 77051520. Its totient is φ = 4478976.

The previous prime is 20407129. The next prime is 20407181. The reversal of 20407140 is 4170402.

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 (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1074051 + ... + 1074069.

It is an arithmetic number, because the mean of its divisors is an integer number (267540).

Almost surely, 2^20407140 is an apocalyptic number.

20407140 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 20407140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38525760).

20407140 is an abundant number, since it is smaller than the sum of its proper divisors (56644380).

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

20407140 is a wasteful number, since it uses less digits than its factorization.

20407140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 20407140 is about 4517.4262583909. The cubic root of 20407140 is about 273.2713158259.

Adding to 20407140 its reverse (4170402), we get a palindrome (24577542).

It can be divided in two parts, 2040 and 7140, that added together give a triangular number (9180 = T₁₃₅).

The spelling of 20407140 in words is "twenty million, four hundred seven thousand, one hundred forty".