21510201055 has 24 divisors (see below), whose sum is σ = 31606832880. Its totient is φ = 13973541120.

The previous prime is 21510201023. The next prime is 21510201073. The reversal of 21510201055 is 55010201512.

It is a happy number.

It is not a de Polignac number, because 21510201055 - 2⁵ = 21510201023 is a prime.

It is a super-2 number, since 2×21510201055² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2305786 + ... + 2315095.

It is an arithmetic number, because the mean of its divisors is an integer number (1316951370).

Almost surely, 2^21510201055 is an apocalyptic number.

21510201055 is a deficient number, since it is larger than the sum of its proper divisors (10096631825).

21510201055 is a wasteful number, since it uses less digits than its factorization.

21510201055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4620919 (or 4620912 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 22.

Adding to 21510201055 its reverse (55010201512), we get a palindrome (76520402567).

The spelling of 21510201055 in words is "twenty-one billion, five hundred ten million, two hundred one thousand, fifty-five".