20121243355 has 8 divisors (see below), whose sum is σ = 24505872912. Its totient is φ = 15856740768.

The previous prime is 20121243343. The next prime is 20121243361. The reversal of 20121243355 is 55334212102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20121243355 - 2²⁵ = 20087688923 is a prime.

It is a super-2 number, since 2×20121243355² (a number of 21 digits) contains 22 as substring.

It is a Duffinian 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, 30031372 + ... + 30032041.

It is an arithmetic number, because the mean of its divisors is an integer number (3063234114).

Almost surely, 2^20121243355 is an apocalyptic number.

20121243355 is a deficient number, since it is larger than the sum of its proper divisors (4384629557).

20121243355 is an equidigital number, since it uses as much as digits as its factorization.

20121243355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60063485.

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 20121243355 its reverse (55334212102), we get a palindrome (75455455457).

The spelling of 20121243355 in words is "twenty billion, one hundred twenty-one million, two hundred forty-three thousand, three hundred fifty-five".