20798681087 has 4 divisors (see below), whose sum is σ = 20823064920. Its totient is φ = 20774297256.

The previous prime is 20798681081. The next prime is 20798681117. The reversal of 20798681087 is 78018689702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20798681087 - 2³⁰ = 19724939263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20798681081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12190637 + ... + 12192342.

It is an arithmetic number, because the mean of its divisors is an integer number (5205766230).

Almost surely, 2^20798681087 is an apocalyptic number.

20798681087 is a deficient number, since it is larger than the sum of its proper divisors (24383833).

20798681087 is an equidigital number, since it uses as much as digits as its factorization.

20798681087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24383832.

The product of its (nonzero) digits is 2709504, while the sum is 56.

The spelling of 20798681087 in words is "twenty billion, seven hundred ninety-eight million, six hundred eighty-one thousand, eighty-seven".