21147648164851 has 8 divisors (see below), whose sum is σ = 22778702920064. Its totient is φ = 19517209493760.

The previous prime is 21147648164849. The next prime is 21147648164873. The reversal of 21147648164851 is 15846184674112.

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 21147648164851 - 2¹ = 21147648164849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21147648164351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153949731 + ... + 154087036.

It is an arithmetic number, because the mean of its divisors is an integer number (2847337865008).

Almost surely, 2^{21147648164851} is an apocalyptic number.

21147648164851 is a deficient number, since it is larger than the sum of its proper divisors (1631054755213).

21147648164851 is a wasteful number, since it uses less digits than its factorization.

21147648164851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308042061.

The product of its digits is 10321920, while the sum is 58.

The spelling of 21147648164851 in words is "twenty-one trillion, one hundred forty-seven billion, six hundred forty-eight million, one hundred sixty-four thousand, eight hundred fifty-one".