20121540420 has 48 divisors (see below), whose sum is σ = 57112110720. Its totient is φ = 5292239616.

The previous prime is 20121540359. The next prime is 20121540469. The reversal of 20121540420 is 2404512102.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2292600 + ... + 2301359.

It is an arithmetic number, because the mean of its divisors is an integer number (1189835640).

Almost surely, 2^20121540420 is an apocalyptic number.

20121540420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121540420 is an abundant number, since it is smaller than the sum of its proper divisors (36990570300).

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

20121540420 is a wasteful number, since it uses less digits than its factorization.

20121540420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4594044 (or 4594042 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The spelling of 20121540420 in words is "twenty billion, one hundred twenty-one million, five hundred forty thousand, four hundred twenty".