21012101000 has 256 divisors, whose sum is σ = 55056568320. Its totient is φ = 7441920000.

The previous prime is 21012100951. The next prime is 21012101009. The reversal of 21012101000 is 10121012.

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 (21012101009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 110010905 + ... + 110011095.

It is an arithmetic number, because the mean of its divisors is an integer number (215064720).

Almost surely, 2^21012101000 is an apocalyptic number.

21012101000 is a gapful number since it is divisible by the number (20) 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 21012101000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27528284160).

21012101000 is an abundant number, since it is smaller than the sum of its proper divisors (34044467320).

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

21012101000 is a wasteful number, since it uses less digits than its factorization.

21012101000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 433 (or 419 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21012101000 its reverse (10121012), we get a palindrome (21022222012).

The spelling of 21012101000 in words is "twenty-one billion, twelve million, one hundred one thousand".