21045551555013 has 16 divisors (see below), whose sum is σ = 28564146389760. Its totient is φ = 13780270554624.

The previous prime is 21045551554981. The next prime is 21045551555057. The reversal of 21045551555013 is 31055515554012.

It is not a de Polignac number, because 21045551555013 - 2⁵ = 21045551554981 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21045551555713) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200990356 + ... + 201095037.

It is an arithmetic number, because the mean of its divisors is an integer number (1785259149360).

Almost surely, 2^{21045551555013} is an apocalyptic number.

It is an amenable number.

21045551555013 is a deficient number, since it is larger than the sum of its proper divisors (7518594834747).

21045551555013 is a wasteful number, since it uses less digits than its factorization.

21045551555013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402085708.

The product of its (nonzero) digits is 375000, while the sum is 42.

The spelling of 21045551555013 in words is "twenty-one trillion, forty-five billion, five hundred fifty-one million, five hundred fifty-five thousand, thirteen".