10212121000 has 128 divisors (see below), whose sum is σ = 25372582560. Its totient is φ = 3833856000.

The previous prime is 10212120979. The next prime is 10212121001. The reversal of 10212121000 is 12121201.

It can be written as a sum of positive squares in 16 ways, for example, as 4251844 + 10207869156 = 2062^2 + 101034^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (10212121001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8856424 + ... + 8857576.

Almost surely, 2^10212121000 is an apocalyptic number.

10212121000 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 10212121000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12686291280).

10212121000 is an abundant number, since it is smaller than the sum of its proper divisors (15160461560).

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

10212121000 is a wasteful number, since it uses less digits than its factorization.

10212121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1712 (or 1698 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 10212121000 its reverse (12121201), we get a palindrome (10224242201).

The spelling of 10212121000 in words is "ten billion, two hundred twelve million, one hundred twenty-one thousand".