11111021000 has 64 divisors (see below), whose sum is σ = 26092974960. Its totient is φ = 4428480000.

The previous prime is 11111020993. The next prime is 11111021003. The reversal of 11111021000 is 12011111.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 78039556 + 11032981444 = 8834^2 + 105038^2 .

It is a Harshad number since it is a multiple of its sum of digits (8).

It is not an unprimeable number, because it can be changed into a prime (11111021003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 261230 + ... + 300770.

Almost surely, 2^11111021000 is an apocalyptic number.

11111021000 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 11111021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13046487480).

11111021000 is an abundant number, since it is smaller than the sum of its proper divisors (14981953960).

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

11111021000 is a wasteful number, since it uses less digits than its factorization.

11111021000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39843 (or 39829 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 8.

Adding to 11111021000 its reverse (12011111), we get a palindrome (11123032111).

The spelling of 11111021000 in words is "eleven billion, one hundred eleven million, twenty-one thousand".