21109289284 has 12 divisors (see below), whose sum is σ = 37939668844. Its totient is φ = 10269383904.

The previous prime is 21109289269. The next prime is 21109289291. The reversal of 21109289284 is 48298290112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17500644100 + 3608645184 = 132290^2 + 60072^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71315019 + ... + 71315314.

Almost surely, 2^21109289284 is an apocalyptic number.

It is an amenable number.

21109289284 is a deficient number, since it is larger than the sum of its proper divisors (16830379560).

21109289284 is a wasteful number, since it uses less digits than its factorization.

21109289284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142630374 (or 142630372 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 46.

It can be divided in two parts, 2110928 and 9284, that added together give a palindrome (2120212).

The spelling of 21109289284 in words is "twenty-one billion, one hundred nine million, two hundred eighty-nine thousand, two hundred eighty-four".