20645000353 has 4 divisors (see below), whose sum is σ = 21542609088. Its totient is φ = 19747391620.

The previous prime is 20645000347. The next prime is 20645000381. The reversal of 20645000353 is 35300054602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 35300054602 = 2 ⋅17650027301.

It is a cyclic number.

It is not a de Polignac number, because 20645000353 - 2¹³ = 20644992161 is a prime.

It is a super-3 number, since 3×20645000353³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20645000333) 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, 448804333 + ... + 448804378.

It is an arithmetic number, because the mean of its divisors is an integer number (5385652272).

Almost surely, 2^20645000353 is an apocalyptic number.

20645000353 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

20645000353 is a deficient number, since it is larger than the sum of its proper divisors (897608735).

20645000353 is an equidigital number, since it uses as much as digits as its factorization.

20645000353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 897608734.

The product of its (nonzero) digits is 10800, while the sum is 28.

Adding to 20645000353 its reverse (35300054602), we get a palindrome (55945054955).

The spelling of 20645000353 in words is "twenty billion, six hundred forty-five million, three hundred fifty-three", and thus it is an aban number.