21242277617 has 4 divisors (see below), whose sum is σ = 23173393776. Its totient is φ = 19311161460.

The previous prime is 21242277611. The next prime is 21242277619. The reversal of 21242277617 is 71677224212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21242277617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21242277611) 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 3 ways as a sum of consecutive naturals, for example, 965558063 + ... + 965558084.

It is an arithmetic number, because the mean of its divisors is an integer number (5793348444).

Almost surely, 2^21242277617 is an apocalyptic number.

It is an amenable number.

21242277617 is a deficient number, since it is larger than the sum of its proper divisors (1931116159).

21242277617 is a wasteful number, since it uses less digits than its factorization.

21242277617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1931116158.

The product of its digits is 131712, while the sum is 41.

The spelling of 21242277617 in words is "twenty-one billion, two hundred forty-two million, two hundred seventy-seven thousand, six hundred seventeen".