21401223204120 has 128 divisors (see below), whose sum is σ = 65298947558400. Its totient is φ = 5609655796736.

The previous prime is 21401223204107. The next prime is 21401223204143. The reversal of 21401223204120 is 2140232210412.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 67079617 + ... + 67397903.

It is an arithmetic number, because the mean of its divisors is an integer number (510148027800).

Almost surely, 2^{21401223204120} is an apocalyptic number.

21401223204120 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 21401223204120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32649473779200).

21401223204120 is an abundant number, since it is smaller than the sum of its proper divisors (43897724354280).

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

21401223204120 is a wasteful number, since it uses less digits than its factorization.

21401223204120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327857 (or 327853 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21401223204120 its reverse (2140232210412), we get a palindrome (23541455414532).

The spelling of 21401223204120 in words is "twenty-one trillion, four hundred one billion, two hundred twenty-three million, two hundred four thousand, one hundred twenty".