21201011011220 has 24 divisors (see below), whose sum is σ = 44522213563464. Its totient is φ = 8480387177856.

The previous prime is 21201011011207. The next prime is 21201011011241. The reversal of 21201011011220 is 2211011010212.

It can be written as a sum of positive squares in 4 ways, for example, as 37220441476 + 21163790569744 = 192926^2 + 4600412^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21201011011195 and 21201011011204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14539682 + ... + 15931238.

It is an arithmetic number, because the mean of its divisors is an integer number (1855092231811).

Almost surely, 2^{21201011011220} is an apocalyptic number.

21201011011220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201011011220 is an abundant number, since it is smaller than the sum of its proper divisors (23321202552244).

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

21201011011220 is a wasteful number, since it uses less digits than its factorization.

21201011011220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2153339 (or 2153337 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21201011011220 its reverse (2211011010212), we get a palindrome (23412022021432).

The spelling of 21201011011220 in words is "twenty-one trillion, two hundred one billion, eleven million, eleven thousand, two hundred twenty".