20729787806 has 96 divisors (see below), whose sum is σ = 41258004480. Its totient is φ = 7726428864.

The previous prime is 20729787803. The next prime is 20729787809. The reversal of 20729787806 is 60878792702.

It is an interprime number because it is at equal distance from previous prime (20729787803) and next prime (20729787809).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20729787803) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1957955 + ... + 1968513.

It is an arithmetic number, because the mean of its divisors is an integer number (429770880).

Almost surely, 2^20729787806 is an apocalyptic number.

20729787806 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20729787806 is a deficient number, since it is larger than the sum of its proper divisors (20528216674).

20729787806 is a wasteful number, since it uses less digits than its factorization.

20729787806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10678 (or 10671 counting only the distinct ones).

The product of its (nonzero) digits is 4741632, while the sum is 56.

The spelling of 20729787806 in words is "twenty billion, seven hundred twenty-nine million, seven hundred eighty-seven thousand, eight hundred six".