21530025342 has 80 divisors (see below), whose sum is σ = 55890581472. Its totient is φ = 6067146240.

The previous prime is 21530025331. The next prime is 21530025347. The reversal of 21530025342 is 24352003512.

It is a happy number.

21530025342 is a `hidden beast` number, since 2 + 15 + 300 + 2 + 5 + 342 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21530025347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 47259 + ... + 212822.

Almost surely, 2^21530025342 is an apocalyptic number.

21530025342 is an abundant number, since it is smaller than the sum of its proper divisors (34360556130).

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

21530025342 is a wasteful number, since it uses less digits than its factorization.

21530025342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260175 (or 260166 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

Adding to 21530025342 its reverse (24352003512), we get a palindrome (45882028854).

The spelling of 21530025342 in words is "twenty-one billion, five hundred thirty million, twenty-five thousand, three hundred forty-two".