21131350025055 has 16 divisors (see below), whose sum is σ = 33854588652384. Its totient is φ = 11255243809280.

The previous prime is 21131350025039. The next prime is 21131350025069. The reversal of 21131350025055 is 55052005313112.

It is a happy number.

It is not a de Polignac number, because 21131350025055 - 2⁴ = 21131350025039 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 925584294 + ... + 925607123.

It is an arithmetic number, because the mean of its divisors is an integer number (2115911790774).

Almost surely, 2^{21131350025055} is an apocalyptic number.

21131350025055 is a deficient number, since it is larger than the sum of its proper divisors (12723238627329).

21131350025055 is a wasteful number, since it uses less digits than its factorization.

21131350025055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1851192186.

The product of its (nonzero) digits is 22500, while the sum is 33.

Adding to 21131350025055 its reverse (55052005313112), we get a palindrome (76183355338167).

The spelling of 21131350025055 in words is "twenty-one trillion, one hundred thirty-one billion, three hundred fifty million, twenty-five thousand, fifty-five".