21615566102401 has 8 divisors (see below), whose sum is σ = 21627143395200. Its totient is φ = 21603991913472.

The previous prime is 21615566102327. The next prime is 21615566102413. The reversal of 21615566102401 is 10420166551612.

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 21615566102401 - 2¹¹ = 21615566100353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21615566102441) 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, 13223425 + ... + 14767873.

It is an arithmetic number, because the mean of its divisors is an integer number (2703392924400).

Almost surely, 2^{21615566102401} is an apocalyptic number.

It is an amenable number.

21615566102401 is a deficient number, since it is larger than the sum of its proper divisors (11577292799).

21615566102401 is a wasteful number, since it uses less digits than its factorization.

21615566102401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1551935.

The product of its (nonzero) digits is 86400, while the sum is 40.

The spelling of 21615566102401 in words is "twenty-one trillion, six hundred fifteen billion, five hundred sixty-six million, one hundred two thousand, four hundred one".