21873610649 has 8 divisors (see below), whose sum is σ = 23884005600. Its totient is φ = 19866863200.

The previous prime is 21873610601. The next prime is 21873610663. The reversal of 21873610649 is 94601637812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21873610649 - 2⁸ = 21873610393 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21873613649) 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, 899324 + ... + 923325.

It is an arithmetic number, because the mean of its divisors is an integer number (2985500700).

Almost surely, 2^21873610649 is an apocalyptic number.

It is an amenable number.

21873610649 is a deficient number, since it is larger than the sum of its proper divisors (2010394951).

21873610649 is a wasteful number, since it uses less digits than its factorization.

21873610649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1823751.

The product of its (nonzero) digits is 435456, while the sum is 47.

The spelling of 21873610649 in words is "twenty-one billion, eight hundred seventy-three million, six hundred ten thousand, six hundred forty-nine".