20442440242397 has 4 divisors (see below), whose sum is σ = 20443171375836. Its totient is φ = 20441709108960.

The previous prime is 20442440242391. The next prime is 20442440242423. The reversal of 20442440242397 is 79324204424402.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4963676540761 + 15478763701636 = 2227931^2 + 3934306^2 .

It is a cyclic number.

It is not a de Polignac number, because 20442440242397 - 2⁴ = 20442440242381 is a prime.

It is a super-2 number, since 2×20442440242397² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20442440242391) 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, 365524778 + ... + 365580699.

It is an arithmetic number, because the mean of its divisors is an integer number (5110792843959).

Almost surely, 2^{20442440242397} is an apocalyptic number.

It is an amenable number.

20442440242397 is a deficient number, since it is larger than the sum of its proper divisors (731133439).

20442440242397 is an equidigital number, since it uses as much as digits as its factorization.

20442440242397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 731133438.

The product of its (nonzero) digits is 3096576, while the sum is 47.

Adding to 20442440242397 its reverse (79324204424402), we get a palindrome (99766644666799).

The spelling of 20442440242397 in words is "twenty trillion, four hundred forty-two billion, four hundred forty million, two hundred forty-two thousand, three hundred ninety-seven".