20121004240 has 40 divisors (see below), whose sum is σ = 46798076160. Its totient is φ = 8045521536.

The previous prime is 20121004207. The next prime is 20121004249. The reversal of 20121004240 is 4240012102.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121004249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187401 + ... + 274519.

It is an arithmetic number, because the mean of its divisors is an integer number (1169951904).

Almost surely, 2^20121004240 is an apocalyptic number.

20121004240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121004240 is an abundant number, since it is smaller than the sum of its proper divisors (26677071920).

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

20121004240 is a wasteful number, since it uses less digits than its factorization.

20121004240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90019 (or 90013 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 20121004240 its reverse (4240012102), we get a palindrome (24361016342).

The spelling of 20121004240 in words is "twenty billion, one hundred twenty-one million, four thousand, two hundred forty".