21011020212210 has 64 divisors (see below), whose sum is σ = 57654473179392. Its totient is φ = 4800498379776.

The previous prime is 21011020212209. The next prime is 21011020212211. The reversal of 21011020212210 is 1221202011012.

It is an interprime number because it is at equal distance from previous prime (21011020212209) and next prime (21011020212211).

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

It is a self number, because there is not a number n which added to its sum of digits gives 21011020212210.

It is not an unprimeable number, because it can be changed into a prime (21011020212211) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20546787 + ... + 21545126.

It is an arithmetic number, because the mean of its divisors is an integer number (900851143428).

Almost surely, 2^{21011020212210} is an apocalyptic number.

21011020212210 is an abundant number, since it is smaller than the sum of its proper divisors (36643452967182).

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

21011020212210 is a wasteful number, since it uses less digits than its factorization.

21011020212210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42094307.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21011020212210 its reverse (1221202011012), we get a palindrome (22232222223222).

The spelling of 21011020212210 in words is "twenty-one trillion, eleven billion, twenty million, two hundred twelve thousand, two hundred ten".