21615554434441 has 8 divisors (see below), whose sum is σ = 23589855792000. Its totient is φ = 19642794902640.

The previous prime is 21615554434399. The next prime is 21615554434613. The reversal of 21615554434441 is 14443445551612.

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 21615554434441 - 2¹⁵ = 21615554401673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21615554432441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 385427121 + ... + 385483198.

It is an arithmetic number, because the mean of its divisors is an integer number (2948731974000).

Almost surely, 2^{21615554434441} is an apocalyptic number.

It is an amenable number.

21615554434441 is a deficient number, since it is larger than the sum of its proper divisors (1974301357559).

21615554434441 is a wasteful number, since it uses less digits than its factorization.

21615554434441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 770912879.

The product of its digits is 4608000, while the sum is 49.

The spelling of 21615554434441 in words is "twenty-one trillion, six hundred fifteen billion, five hundred fifty-four million, four hundred thirty-four thousand, four hundred forty-one".