21660400162055 has 8 divisors (see below), whose sum is σ = 27122588029152. Its totient is φ = 16574914906528.

The previous prime is 21660400162043. The next prime is 21660400162069. The reversal of 21660400162055 is 55026100406612.

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 21660400162055 - 2²² = 21660395967751 is a prime.

It is a Duffinian number.

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, 94175652764 + ... + 94175652993.

It is an arithmetic number, because the mean of its divisors is an integer number (3390323503644).

Almost surely, 2^{21660400162055} is an apocalyptic number.

21660400162055 is a deficient number, since it is larger than the sum of its proper divisors (5462187867097).

21660400162055 is a wasteful number, since it uses less digits than its factorization.

21660400162055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188351305785.

The product of its (nonzero) digits is 86400, while the sum is 38.

Adding to 21660400162055 its reverse (55026100406612), we get a palindrome (76686500568667).

The spelling of 21660400162055 in words is "twenty-one trillion, six hundred sixty billion, four hundred million, one hundred sixty-two thousand, fifty-five".