21545424414 has 112 divisors (see below), whose sum is σ = 51299036880. Its totient is φ = 6764653440.

The previous prime is 21545424403. The next prime is 21545424443. The reversal of 21545424414 is 41442454512.

21545424414 is a `hidden beast` number, since 21 + 54 + 542 + 4 + 41 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 5011914 + ... + 5016210.

It is an arithmetic number, because the mean of its divisors is an integer number (458027115).

Almost surely, 2^21545424414 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21545424414, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25649518440).

21545424414 is an abundant number, since it is smaller than the sum of its proper divisors (29753612466).

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

21545424414 is a wasteful number, since it uses less digits than its factorization.

21545424414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4517 (or 4502 counting only the distinct ones).

The product of its digits is 102400, while the sum is 36.

Adding to 21545424414 its reverse (41442454512), we get a palindrome (62987878926).

The spelling of 21545424414 in words is "twenty-one billion, five hundred forty-five million, four hundred twenty-four thousand, four hundred fourteen".