21121455054 has 16 divisors (see below), whose sum is σ = 48277611648. Its totient is φ = 6034701432.

The previous prime is 21121455041. The next prime is 21121455101. The reversal of 21121455054 is 45055412112.

It is a super-2 number, since 2×21121455054² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 251445852 + ... + 251445935.

It is an arithmetic number, because the mean of its divisors is an integer number (3017350728).

Almost surely, 2^21121455054 is an apocalyptic number.

21121455054 is an abundant number, since it is smaller than the sum of its proper divisors (27156156594).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21121455054 is a wasteful number, since it uses less digits than its factorization.

21121455054 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502891799.

The product of its (nonzero) digits is 8000, while the sum is 30.

Adding to 21121455054 its reverse (45055412112), we get a palindrome (66176867166).

The spelling of 21121455054 in words is "twenty-one billion, one hundred twenty-one million, four hundred fifty-five thousand, fifty-four".