21535513001400 has 192 divisors, whose sum is σ = 69519536179200. Its totient is φ = 5508054720000.

The previous prime is 21535513001399. The next prime is 21535513001407. The reversal of 21535513001400 is 410031553512.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21535513001407) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1470856 + ... + 6725655.

It is an arithmetic number, because the mean of its divisors is an integer number (362080917600).

Almost surely, 2^{21535513001400} is an apocalyptic number.

21535513001400 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 21535513001400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34759768089600).

21535513001400 is an abundant number, since it is smaller than the sum of its proper divisors (47984023177800).

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

21535513001400 is a wasteful number, since it uses less digits than its factorization.

21535513001400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8196710 (or 8196701 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 30.

Adding to 21535513001400 its reverse (410031553512), we get a palindrome (21945544554912).

The spelling of 21535513001400 in words is "twenty-one trillion, five hundred thirty-five billion, five hundred thirteen million, one thousand, four hundred".