20121122212551 has 8 divisors (see below), whose sum is σ = 29809069944560. Its totient is φ = 13414081475016.

The previous prime is 20121122212547. The next prime is 20121122212559. The reversal of 20121122212551 is 15521222112102.

It is a happy number.

20121122212551 is a `hidden beast` number, since 201 + 211 + 2 + 221 + 25 + 5 + 1 = 666.

It is not a de Polignac number, because 20121122212551 - 2² = 20121122212547 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 745226748613 = 20121122212551 / (2 + 0 + 1 + 2 + 1 + 1 + 2 + 2 + 2 + 1 + 2 + 5 + 5 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121122212559) 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, 372613374280 + ... + 372613374333.

It is an arithmetic number, because the mean of its divisors is an integer number (3726133743070).

Almost surely, 2^{20121122212551} is an apocalyptic number.

20121122212551 is a deficient number, since it is larger than the sum of its proper divisors (9687947732009).

20121122212551 is an equidigital number, since it uses as much as digits as its factorization.

20121122212551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 745226748622 (or 745226748616 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 27.

Adding to 20121122212551 its reverse (15521222112102), we get a palindrome (35642344324653).

The spelling of 20121122212551 in words is "twenty trillion, one hundred twenty-one billion, one hundred twenty-two million, two hundred twelve thousand, five hundred fifty-one".