1211121212010 has 64 divisors (see below), whose sum is σ = 2989510602624. Its totient is φ = 313788384000.

The previous prime is 1211121212009. The next prime is 1211121212011. The reversal of 1211121212010 is 102121211121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1211121212009) and next prime (1211121212011).

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

It is not an unprimeable number, because it can be changed into a prime (1211121212011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 136 + ... + 1556355.

It is an arithmetic number, because the mean of its divisors is an integer number (46711103166).

Almost surely, 2^{1211121212010} is an apocalyptic number.

1211121212010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211121212010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1494755301312).

1211121212010 is an abundant number, since it is smaller than the sum of its proper divisors (1778389390614).

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

1211121212010 is a wasteful number, since it uses less digits than its factorization.

1211121212010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557239.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1211121212010 its reverse (102121211121), we get a palindrome (1313242423131).

The spelling of 1211121212010 in words is "one trillion, two hundred eleven billion, one hundred twenty-one million, two hundred twelve thousand, ten".