21010212212280 has 128 divisors (see below), whose sum is σ = 63834825600000. Its totient is φ = 5531253871104.

The previous prime is 21010212212279. The next prime is 21010212212281. The reversal of 21010212212280 is 8221221201012.

It is an interprime number because it is at equal distance from previous prime (21010212212279) and next prime (21010212212281).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21010212212280.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010212212281) 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, 100279071 + ... + 100488369.

It is an arithmetic number, because the mean of its divisors is an integer number (498709575000).

Almost surely, 2^{21010212212280} is an apocalyptic number.

21010212212280 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 21010212212280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31917412800000).

21010212212280 is an abundant number, since it is smaller than the sum of its proper divisors (42824613387720).

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

21010212212280 is a wasteful number, since it uses less digits than its factorization.

21010212212280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219981 (or 219977 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 24.

Adding to 21010212212280 its reverse (8221221201012), we get a palindrome (29231433413292).

The spelling of 21010212212280 in words is "twenty-one trillion, ten billion, two hundred twelve million, two hundred twelve thousand, two hundred eighty".