21011010012 has 24 divisors (see below), whose sum is σ = 54472989200. Its totient is φ = 7003669968.

The previous prime is 21011010011. The next prime is 21011010029. The reversal of 21011010012 is 21001011012.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21011009976 and 21011010003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011010011) 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 7 ways as a sum of consecutive naturals, for example, 97273087 + ... + 97273302.

Almost surely, 2^21011010012 is an apocalyptic number.

It is an amenable number.

21011010012 is an abundant number, since it is smaller than the sum of its proper divisors (33461979188).

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

21011010012 is a wasteful number, since it uses less digits than its factorization.

21011010012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194546402 (or 194546394 counting only the distinct ones).

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

Adding to 21011010012 its reverse (21001011012), we get a palindrome (42012021024).

The spelling of 21011010012 in words is "twenty-one billion, eleven million, ten thousand, twelve".