21649419892 has 24 divisors (see below), whose sum is σ = 38332709352. Its totient is φ = 10697616000.

The previous prime is 21649419877. The next prime is 21649419899. The reversal of 21649419892 is 29891494612.

It can be written as a sum of positive squares in 4 ways, for example, as 1447345936 + 20202073956 = 38044^2 + 142134^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21649419899) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 169038 + ... + 268090.

It is an arithmetic number, because the mean of its divisors is an integer number (1597196223).

Almost surely, 2^21649419892 is an apocalyptic number.

It is an amenable number.

21649419892 is a deficient number, since it is larger than the sum of its proper divisors (16683289460).

21649419892 is a wasteful number, since it uses less digits than its factorization.

21649419892 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99699 (or 99697 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 55.

The spelling of 21649419892 in words is "twenty-one billion, six hundred forty-nine million, four hundred nineteen thousand, eight hundred ninety-two".