21541355405 has 8 divisors (see below), whose sum is σ = 25877760000. Its totient is φ = 17214328656.

The previous prime is 21541355399. The next prime is 21541355441. The reversal of 21541355405 is 50455314512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21541355405 - 2¹² = 21541351309 is a prime.

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, 2339405 + ... + 2348594.

It is an arithmetic number, because the mean of its divisors is an integer number (3234720000).

Almost surely, 2^21541355405 is an apocalyptic number.

It is an amenable number.

21541355405 is a deficient number, since it is larger than the sum of its proper divisors (4336404595).

21541355405 is an equidigital number, since it uses as much as digits as its factorization.

21541355405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4688923.

The product of its (nonzero) digits is 60000, while the sum is 35.

Adding to 21541355405 its reverse (50455314512), we get a palindrome (71996669917).

The spelling of 21541355405 in words is "twenty-one billion, five hundred forty-one million, three hundred fifty-five thousand, four hundred five".