21649589826 has 16 divisors (see below), whose sum is σ = 43313596128. Its totient is φ = 7214127200.

The previous prime is 21649589789. The next prime is 21649589833. The reversal of 21649589826 is 62898594612.

It is a self number, because there is not a number n which added to its sum of digits gives 21649589826.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 581115 + ... + 617246.

It is an arithmetic number, because the mean of its divisors is an integer number (2707099758).

Almost surely, 2^21649589826 is an apocalyptic number.

21649589826 is an abundant number, since it is smaller than the sum of its proper divisors (21664006302).

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

21649589826 is a wasteful number, since it uses less digits than its factorization.

21649589826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1201377.

The product of its digits is 14929920, while the sum is 60.

The spelling of 21649589826 in words is "twenty-one billion, six hundred forty-nine million, five hundred eighty-nine thousand, eight hundred twenty-six".