20452781817 has 48 divisors (see below), whose sum is σ = 32632419456. Its totient is φ = 12263904000.

The previous prime is 20452781813. The next prime is 20452781861. The reversal of 20452781817 is 71818725402.

It is not a de Polignac number, because 20452781817 - 2² = 20452781813 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20452781813) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4655692 + ... + 4660082.

It is an arithmetic number, because the mean of its divisors is an integer number (679842072).

Almost surely, 2^20452781817 is an apocalyptic number.

It is an amenable number.

20452781817 is a deficient number, since it is larger than the sum of its proper divisors (12179637639).

20452781817 is a wasteful number, since it uses less digits than its factorization.

20452781817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5422 (or 5419 counting only the distinct ones).

The product of its (nonzero) digits is 250880, while the sum is 45.

The spelling of 20452781817 in words is "twenty billion, four hundred fifty-two million, seven hundred eighty-one thousand, eight hundred seventeen".