20120040 has 48 divisors (see below), whose sum is σ = 65391300. Its totient is φ = 5365248.

The previous prime is 20120029. The next prime is 20120047. The reversal of 20120040 is 4002102.

It can be written as a sum of positive squares in 2 ways, for example, as 19660356 + 459684 = 4434^2 + 678^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (20120047) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27585 + ... + 28304.

Almost surely, 2^20120040 is an apocalyptic number.

20120040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20120040 is an abundant number, since it is smaller than the sum of its proper divisors (45271260).

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

20120040 is a wasteful number, since it uses less digits than its factorization.

20120040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55906 (or 55899 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 20120040 is about 4485.5367571786. The cubic root of 20120040 is about 271.9837432614.

Adding to 20120040 its reverse (4002102), we get a palindrome (24122142).

The spelling of 20120040 in words is "twenty million, one hundred twenty thousand, forty".