21542514542542 has 16 divisors (see below), whose sum is σ = 36930086311392. Its totient is φ = 9232490887200.

The previous prime is 21542514542539. The next prime is 21542514542561. The reversal of 21542514542542 is 24524541524512.

It is a junction number, because it is equal to n+sod(n) for n = 21542514542492 and 21542514542501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12758688 + ... + 14348140.

It is an arithmetic number, because the mean of its divisors is an integer number (2308130394462).

Almost surely, 2^{21542514542542} is an apocalyptic number.

21542514542542 is a deficient number, since it is larger than the sum of its proper divisors (15387571768850).

21542514542542 is a wasteful number, since it uses less digits than its factorization.

21542514542542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2557563.

The product of its digits is 2560000, while the sum is 46.

The spelling of 21542514542542 in words is "twenty-one trillion, five hundred forty-two billion, five hundred fourteen million, five hundred forty-two thousand, five hundred forty-two".