21116151515055 has 32 divisors (see below), whose sum is σ = 34940173989888. Its totient is φ = 10878513321600.

The previous prime is 21116151515029. The next prime is 21116151515057. The reversal of 21116151515055 is 55051515161112.

It is not a de Polignac number, because 21116151515055 - 2⁵ = 21116151515023 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21116151515057) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 41718009 + ... + 42221138.

It is an arithmetic number, because the mean of its divisors is an integer number (1091880437184).

Almost surely, 2^{21116151515055} is an apocalyptic number.

21116151515055 is a deficient number, since it is larger than the sum of its proper divisors (13824022474833).

21116151515055 is a wasteful number, since it uses less digits than its factorization.

21116151515055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83939727.

The product of its (nonzero) digits is 37500, while the sum is 39.

Adding to 21116151515055 its reverse (55051515161112), we get a palindrome (76167666676167).

The spelling of 21116151515055 in words is "twenty-one trillion, one hundred sixteen billion, one hundred fifty-one million, five hundred fifteen thousand, fifty-five".