21355410606400 has 84 divisors (see below), whose sum is σ = 56589784757212. Its totient is φ = 7885074677760.

The previous prime is 21355410606389. The next prime is 21355410606401. The reversal of 21355410606400 is 460601455312.

It can be written as a sum of positive squares in 6 ways, for example, as 945110620224 + 20410299986176 = 972168^2 + 4517776^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21355410606400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21355410606401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 513330417 + ... + 513372016.

Almost surely, 2^{21355410606400} is an apocalyptic number.

21355410606400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21355410606400 is an abundant number, since it is smaller than the sum of its proper divisors (35234374150812).

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

21355410606400 is a wasteful number, since it uses less digits than its factorization.

21355410606400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026702468 (or 1026702453 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 37.

The spelling of 21355410606400 in words is "twenty-one trillion, three hundred fifty-five billion, four hundred ten million, six hundred six thousand, four hundred".