21254100222655 has 4 divisors (see below), whose sum is σ = 25504920267192. Its totient is φ = 17003280178120.

The previous prime is 21254100222569. The next prime is 21254100222659. The reversal of 21254100222655 is 55622200145212.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21254100222655 - 2⁷ = 21254100222527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21254100222659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2125410022261 + ... + 2125410022270.

It is an arithmetic number, because the mean of its divisors is an integer number (6376230066798).

Almost surely, 2^{21254100222655} is an apocalyptic number.

21254100222655 is a deficient number, since it is larger than the sum of its proper divisors (4250820044537).

21254100222655 is an equidigital number, since it uses as much as digits as its factorization.

21254100222655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4250820044536.

The product of its (nonzero) digits is 96000, while the sum is 37.

Adding to 21254100222655 its reverse (55622200145212), we get a palindrome (76876300367867).

The spelling of 21254100222655 in words is "twenty-one trillion, two hundred fifty-four billion, one hundred million, two hundred twenty-two thousand, six hundred fifty-five".