21554101051 has 16 divisors (see below), whose sum is σ = 24902152704. Its totient is φ = 18273703104.

The previous prime is 21554101043. The next prime is 21554101057. The reversal of 21554101051 is 15010145512.

It is a cyclic number.

It is not a de Polignac number, because 21554101051 - 2³ = 21554101043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21554101057) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 600456 + ... + 635338.

It is an arithmetic number, because the mean of its divisors is an integer number (1556384544).

Almost surely, 2^21554101051 is an apocalyptic number.

21554101051 is a deficient number, since it is larger than the sum of its proper divisors (3348051653).

21554101051 is a wasteful number, since it uses less digits than its factorization.

21554101051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35850.

The product of its (nonzero) digits is 1000, while the sum is 25.

Adding to 21554101051 its reverse (15010145512), we get a palindrome (36564246563).

The spelling of 21554101051 in words is "twenty-one billion, five hundred fifty-four million, one hundred one thousand, fifty-one".