21751637117 has 8 divisors (see below), whose sum is σ = 24874850112. Its totient is φ = 18632383200.

The previous prime is 21751637099. The next prime is 21751637143. The reversal of 21751637117 is 71173615712.

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 21751637117 - 2¹⁸ = 21751374973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21751637617) 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, 977984 + ... + 999977.

It is an arithmetic number, because the mean of its divisors is an integer number (3109356264).

Almost surely, 2^21751637117 is an apocalyptic number.

It is an amenable number.

21751637117 is a deficient number, since it is larger than the sum of its proper divisors (3123212995).

21751637117 is a wasteful number, since it uses less digits than its factorization.

21751637117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1979539.

The product of its digits is 61740, while the sum is 41.

The spelling of 21751637117 in words is "twenty-one billion, seven hundred fifty-one million, six hundred thirty-seven thousand, one hundred seventeen".