1212111000 has 128 divisors (see below), whose sum is σ = 4202078400. Its totient is φ = 323222400.

The previous prime is 1212110989. The next prime is 1212111037. The reversal of 1212111000 is 1112121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4554 + ... + 49446.

Almost surely, 2^1212111000 is an apocalyptic number.

1212111000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1212111000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2101039200).

1212111000 is an abundant number, since it is smaller than the sum of its proper divisors (2989967400).

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

1212111000 is a wasteful number, since it uses less digits than its factorization.

1212111000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44923 (or 44903 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 1212111000 is about 34815.3845304055. The cubic root of 1212111000 is about 1066.2215699390.

Adding to 1212111000 its reverse (1112121), we get a palindrome (1213223121).

The spelling of 1212111000 in words is "one billion, two hundred twelve million, one hundred eleven thousand".