20011221240 has 32 divisors (see below), whose sum is σ = 60033664080. Its totient is φ = 5336325632.

The previous prime is 20011221239. The next prime is 20011221253. The reversal of 20011221240 is 4212211002.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 83379969 + ... + 83380208.

Almost surely, 2^20011221240 is an apocalyptic number.

20011221240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20011221240 is an abundant number, since it is smaller than the sum of its proper divisors (40022442840).

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

20011221240 is a wasteful number, since it uses less digits than its factorization.

20011221240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166760191 (or 166760187 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 20011221240 its reverse (4212211002), we get a palindrome (24223432242).

The spelling of 20011221240 in words is "twenty billion, eleven million, two hundred twenty-one thousand, two hundred forty".