20423444343653 has 4 divisors (see below), whose sum is σ = 21994478523948. Its totient is φ = 18852410163360.

The previous prime is 20423444343559. The next prime is 20423444343677. The reversal of 20423444343653 is 35634344432402.

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 3954919735204 + 16468524608449 = 1988698^2 + 4058143^2 .

It is a cyclic number.

It is not a de Polignac number, because 20423444343653 - 2⁴⁴ = 2831258299237 is a prime.

It is a super-2 number, since 2×20423444343653² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20423444343598 and 20423444343607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20423444343353) 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, 785517090128 + ... + 785517090153.

It is an arithmetic number, because the mean of its divisors is an integer number (5498619630987).

Almost surely, 2^{20423444343653} is an apocalyptic number.

It is an amenable number.

20423444343653 is a deficient number, since it is larger than the sum of its proper divisors (1571034180295).

20423444343653 is a wasteful number, since it uses less digits than its factorization.

20423444343653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1571034180294.

The product of its (nonzero) digits is 9953280, while the sum is 47.

The spelling of 20423444343653 in words is "twenty trillion, four hundred twenty-three billion, four hundred forty-four million, three hundred forty-three thousand, six hundred fifty-three".