20781732307 has 8 divisors (see below), whose sum is σ = 23758463232. Its totient is φ = 17806979400.

The previous prime is 20781732287. The next prime is 20781732341. The reversal of 20781732307 is 70323718702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20781732307 - 2²³ = 20773343699 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20781732307.

It is not an unprimeable number, because it can be changed into a prime (20781732347) 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, 471919 + ... + 514072.

It is an arithmetic number, because the mean of its divisors is an integer number (2969807904).

Almost surely, 2^20781732307 is an apocalyptic number.

20781732307 is a deficient number, since it is larger than the sum of its proper divisors (2976730925).

20781732307 is an equidigital number, since it uses as much as digits as its factorization.

20781732307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989009.

The product of its (nonzero) digits is 98784, while the sum is 40.

The spelling of 20781732307 in words is "twenty billion, seven hundred eighty-one million, seven hundred thirty-two thousand, three hundred seven".