21285819654 has 32 divisors (see below), whose sum is σ = 46522359936. Its totient is φ = 6439057920.

The previous prime is 21285819619. The next prime is 21285819671. The reversal of 21285819654 is 45691858212.

It is a super-2 number, since 2×21285819654² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21285819597 and 21285819606.

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, 241392 + ... + 317555.

It is an arithmetic number, because the mean of its divisors is an integer number (1453823748).

Almost surely, 2^21285819654 is an apocalyptic number.

21285819654 is an abundant number, since it is smaller than the sum of its proper divisors (25236540282).

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

21285819654 is a wasteful number, since it uses less digits than its factorization.

21285819654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559540.

The product of its digits is 1382400, while the sum is 51.

The spelling of 21285819654 in words is "twenty-one billion, two hundred eighty-five million, eight hundred nineteen thousand, six hundred fifty-four".