20636574253 has 4 divisors (see below), whose sum is σ = 21722709760. Its totient is φ = 19550438748.

The previous prime is 20636574163. The next prime is 20636574281. The reversal of 20636574253 is 35247563602.

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: 35247563602 = 2 ⋅17623781801.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20636574253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20636574293) 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, 543067725 + ... + 543067762.

It is an arithmetic number, because the mean of its divisors is an integer number (5430677440).

Almost surely, 2^20636574253 is an apocalyptic number.

It is an amenable number.

20636574253 is a deficient number, since it is larger than the sum of its proper divisors (1086135507).

20636574253 is a wasteful number, since it uses less digits than its factorization.

20636574253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1086135506.

The product of its (nonzero) digits is 907200, while the sum is 43.

The spelling of 20636574253 in words is "twenty billion, six hundred thirty-six million, five hundred seventy-four thousand, two hundred fifty-three".