20440857731 has 8 divisors (see below), whose sum is σ = 23496016224. Its totient is φ = 17419458240.

The previous prime is 20440857721. The next prime is 20440857739. The reversal of 20440857731 is 13775804402.

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 20440857731 - 2¹⁴ = 20440841347 is a prime.

It is a super-2 number, since 2×20440857731² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20440857739) 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 7 ways as a sum of consecutive naturals, for example, 8438450 + ... + 8440871.

It is an arithmetic number, because the mean of its divisors is an integer number (2937002028).

Almost surely, 2^20440857731 is an apocalyptic number.

20440857731 is a deficient number, since it is larger than the sum of its proper divisors (3055158493).

20440857731 is a wasteful number, since it uses less digits than its factorization.

20440857731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16879501.

The product of its (nonzero) digits is 188160, while the sum is 41.

The spelling of 20440857731 in words is "twenty billion, four hundred forty million, eight hundred fifty-seven thousand, seven hundred thirty-one".