20818346682821 has 8 divisors (see below), whose sum is σ = 21467710527744. Its totient is φ = 20177583683760.

The previous prime is 20818346682797. The next prime is 20818346682823. The reversal of 20818346682821 is 12828664381802.

It is a happy number.

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 20818346682821 - 2³⁸ = 20543468775877 is a prime.

It is a super-2 number, since 2×20818346682821² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20818346682823) 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, 2150206550 + ... + 2150216231.

It is an arithmetic number, because the mean of its divisors is an integer number (2683463815968).

Almost surely, 2^{20818346682821} is an apocalyptic number.

It is an amenable number.

20818346682821 is a deficient number, since it is larger than the sum of its proper divisors (649363844923).

20818346682821 is a wasteful number, since it uses less digits than its factorization.

20818346682821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4300422931.

The product of its (nonzero) digits is 14155776, while the sum is 59.

The spelling of 20818346682821 in words is "twenty trillion, eight hundred eighteen billion, three hundred forty-six million, six hundred eighty-two thousand, eight hundred twenty-one".