20645485838 has 4 divisors (see below), whose sum is σ = 30968228760. Its totient is φ = 10322742918.

The previous prime is 20645485829. The next prime is 20645485853. The reversal of 20645485838 is 83858454602.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20645485838.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5161371458 + ... + 5161371461.

It is an arithmetic number, because the mean of its divisors is an integer number (7742057190).

Almost surely, 2^20645485838 is an apocalyptic number.

20645485838 is a deficient number, since it is larger than the sum of its proper divisors (10322742922).

20645485838 is a wasteful number, since it uses less digits than its factorization.

20645485838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10322742921.

The product of its (nonzero) digits is 7372800, while the sum is 53.

It can be divided in two parts, 206454 and 85838, that added together give a palindrome (292292).

The spelling of 20645485838 in words is "twenty billion, six hundred forty-five million, four hundred eighty-five thousand, eight hundred thirty-eight".