21404512685 has 32 divisors (see below), whose sum is σ = 26692848000. Its totient is φ = 16465075200.

The previous prime is 21404512673. The next prime is 21404512699. The reversal of 21404512685 is 58621540412.

It is a happy number.

It is not a de Polignac number, because 21404512685 - 2⁶ = 21404512621 is a prime.

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 31 ways as a sum of consecutive naturals, for example, 8489225 + ... + 8491745.

It is an arithmetic number, because the mean of its divisors is an integer number (834151500).

Almost surely, 2^21404512685 is an apocalyptic number.

It is an amenable number.

21404512685 is a deficient number, since it is larger than the sum of its proper divisors (5288335315).

21404512685 is a wasteful number, since it uses less digits than its factorization.

21404512685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3149.

The product of its (nonzero) digits is 76800, while the sum is 38.

The spelling of 21404512685 in words is "twenty-one billion, four hundred four million, five hundred twelve thousand, six hundred eighty-five".