21321003402144 has 120 divisors (see below), whose sum is σ = 62860852091268. Its totient is φ = 7089277593600.

The previous prime is 21321003402007. The next prime is 21321003402151. The reversal of 21321003402144 is 44120430012312.

21321003402144 is a `hidden beast` number, since 2 + 1 + 3 + 2 + 100 + 340 + 214 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20619409539600 + 701593862544 = 4540860^2 + 837612^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 9217087 + ... + 11295870.

Almost surely, 2^{21321003402144} is an apocalyptic number.

21321003402144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21321003402144 is an abundant number, since it is smaller than the sum of its proper divisors (41539848689124).

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

21321003402144 is a wasteful number, since it uses less digits than its factorization.

21321003402144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20513380 (or 20513363 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 21321003402144 its reverse (44120430012312), we get a palindrome (65441433414456).

The spelling of 21321003402144 in words is "twenty-one trillion, three hundred twenty-one billion, three million, four hundred two thousand, one hundred forty-four".