21535250142 has 64 divisors (see below), whose sum is σ = 51925985280. Its totient is φ = 5816507616.

The previous prime is 21535250141. The next prime is 21535250147. The reversal of 21535250142 is 24105253512.

It is a super-2 number, since 2×21535250142² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21535250141) 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 31 ways as a sum of consecutive naturals, for example, 343773 + ... + 401559.

It is an arithmetic number, because the mean of its divisors is an integer number (811343520).

Almost surely, 2^21535250142 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21535250142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25962992640).

21535250142 is an abundant number, since it is smaller than the sum of its proper divisors (30390735138).

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

21535250142 is a wasteful number, since it uses less digits than its factorization.

21535250142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58285.

The product of its (nonzero) digits is 12000, while the sum is 30.

The spelling of 21535250142 in words is "twenty-one billion, five hundred thirty-five million, two hundred fifty thousand, one hundred forty-two".