21861096436 has 12 divisors (see below), whose sum is σ = 38261537860. Its totient is φ = 10929228480.

The previous prime is 21861096427. The next prime is 21861096463. The reversal of 21861096436 is 63469016812.

It can be written as a sum of positive squares in 2 ways, for example, as 15006250000 + 6854846436 = 122500^2 + 82794^2 .

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 3 ways as a sum of consecutive naturals, for example, 292185 + ... + 359296.

Almost surely, 2^21861096436 is an apocalyptic number.

It is an amenable number.

21861096436 is a deficient number, since it is larger than the sum of its proper divisors (16400441424).

21861096436 is a wasteful number, since it uses less digits than its factorization.

21861096436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 659874 (or 659872 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 46.

The spelling of 21861096436 in words is "twenty-one billion, eight hundred sixty-one million, ninety-six thousand, four hundred thirty-six".