1211101212210 has 128 divisors (see below), whose sum is σ = 3061107624960. Its totient is φ = 306365235456.

The previous prime is 1211101212199. The next prime is 1211101212239. The reversal of 1211101212210 is 122121011121.

It is a happy number.

It is a super-2 number, since 2×1211101212210² (a number of 25 digits) contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1211101212210.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6221272 + ... + 6412988.

It is an arithmetic number, because the mean of its divisors is an integer number (23914903320).

Almost surely, 2^{1211101212210} is an apocalyptic number.

1211101212210 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 1211101212210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1530553812480).

1211101212210 is an abundant number, since it is smaller than the sum of its proper divisors (1850006412750).

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

1211101212210 is a wasteful number, since it uses less digits than its factorization.

1211101212210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191912.

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

Adding to 1211101212210 its reverse (122121011121), we get a palindrome (1333222223331).

The spelling of 1211101212210 in words is "one trillion, two hundred eleven billion, one hundred one million, two hundred twelve thousand, two hundred ten".