21361635254 has 32 divisors (see below), whose sum is σ = 33078217536. Its totient is φ = 10339924480.

The previous prime is 21361635221. The next prime is 21361635283. The reversal of 21361635254 is 45253616312.

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 (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6054839 + ... + 6058365.

It is an arithmetic number, because the mean of its divisors is an integer number (1033694298).

Almost surely, 2^21361635254 is an apocalyptic number.

21361635254 is a deficient number, since it is larger than the sum of its proper divisors (11716582282).

21361635254 is a wasteful number, since it uses less digits than its factorization.

21361635254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4120.

The product of its digits is 129600, while the sum is 38.

The spelling of 21361635254 in words is "twenty-one billion, three hundred sixty-one million, six hundred thirty-five thousand, two hundred fifty-four".