20818824477 has 16 divisors (see below), whose sum is σ = 30853286208. Its totient is φ = 12379402880.

The previous prime is 20818824437. The next prime is 20818824479. The reversal of 20818824477 is 77442881802.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20818824477 - 2¹⁶ = 20818758941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20818824479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5949888 + ... + 5953385.

It is an arithmetic number, because the mean of its divisors is an integer number (1928330388).

Almost surely, 2^20818824477 is an apocalyptic number.

It is an amenable number.

20818824477 is a deficient number, since it is larger than the sum of its proper divisors (10034461731).

20818824477 is a wasteful number, since it uses less digits than its factorization.

20818824477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11903340.

The product of its (nonzero) digits is 1605632, while the sum is 51.

The spelling of 20818824477 in words is "twenty billion, eight hundred eighteen million, eight hundred twenty-four thousand, four hundred seventy-seven".