21551140552011 has 96 divisors (see below), whose sum is σ = 36750792499200. Its totient is φ = 11148756252480.

The previous prime is 21551140551959. The next prime is 21551140552037. The reversal of 21551140552011 is 11025504115512.

It is a happy number.

It is not a de Polignac number, because 21551140552011 - 2¹¹ = 21551140549963 is a prime.

It is a super-2 number, since 2×21551140552011² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21551140552411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 66582876 + ... + 66905766.

It is an arithmetic number, because the mean of its divisors is an integer number (382820755200).

Almost surely, 2^{21551140552011} is an apocalyptic number.

21551140552011 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21551140552011 is a deficient number, since it is larger than the sum of its proper divisors (15199651947189).

21551140552011 is a wasteful number, since it uses less digits than its factorization.

21551140552011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323989 (or 323982 counting only the distinct ones).

The product of its (nonzero) digits is 10000, while the sum is 33.

Adding to 21551140552011 its reverse (11025504115512), we get a palindrome (32576644667523).

The spelling of 21551140552011 in words is "twenty-one trillion, five hundred fifty-one billion, one hundred forty million, five hundred fifty-two thousand, eleven".