21102121211010 has 128 divisors (see below), whose sum is σ = 58038077988864. Its totient is φ = 4810195272960.

The previous prime is 21102121211009. The next prime is 21102121211089. The reversal of 21102121211010 is 1011212120112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

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, 114703959 + ... + 114887781.

It is an arithmetic number, because the mean of its divisors is an integer number (453422484288).

Almost surely, 2^{21102121211010} is an apocalyptic number.

21102121211010 is an abundant number, since it is smaller than the sum of its proper divisors (36935956777854).

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

21102121211010 is a wasteful number, since it uses less digits than its factorization.

21102121211010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185328.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21102121211010 its reverse (1011212120112), we get a palindrome (22113333331122).

The spelling of 21102121211010 in words is "twenty-one trillion, one hundred two billion, one hundred twenty-one million, two hundred eleven thousand, ten".