20120405240 has 32 divisors (see below), whose sum is σ = 48753290880. Its totient is φ = 7429072512.

The previous prime is 20120405209. The next prime is 20120405339. The reversal of 20120405240 is 4250402102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19346024 + ... + 19347063.

It is an arithmetic number, because the mean of its divisors is an integer number (1523540340).

Almost surely, 2^20120405240 is an apocalyptic number.

20120405240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20120405240 is an abundant number, since it is smaller than the sum of its proper divisors (28632885640).

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

20120405240 is a wasteful number, since it uses less digits than its factorization.

20120405240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38693111 (or 38693107 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

Adding to 20120405240 its reverse (4250402102), we get a palindrome (24370807342).

The spelling of 20120405240 in words is "twenty billion, one hundred twenty million, four hundred five thousand, two hundred forty".