1012121100 has 108 divisors (see below), whose sum is σ = 3246339096. Its totient is φ = 263612160.

The previous prime is 1012121081. The next prime is 1012121113. The reversal of 1012121100 is 11212101.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 25624 + ... + 51776.

Almost surely, 2^1012121100 is an apocalyptic number.

1012121100 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 1012121100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1623169548).

1012121100 is an abundant number, since it is smaller than the sum of its proper divisors (2234217996).

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

1012121100 is a wasteful number, since it uses less digits than its factorization.

1012121100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26216 (or 26206 counting only the distinct ones).

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

The square root of 1012121100 is about 31813.8507571781. The cubic root of 1012121100 is about 1004.0241511521.

Adding to 1012121100 its reverse (11212101), we get a palindrome (1023333201).

The spelling of 1012121100 in words is "one billion, twelve million, one hundred twenty-one thousand, one hundred".