20487836747 has 4 divisors (see below), whose sum is σ = 23414670576. Its totient is φ = 17561002920.

The previous prime is 20487836701. The next prime is 20487836771. The reversal of 20487836747 is 74763878402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74763878402 = 2 ⋅37381939201.

It is a cyclic number.

It is not a de Polignac number, because 20487836747 - 2²⁶ = 20420727883 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20487836692 and 20487836701.

It is not an unprimeable number, because it can be changed into a prime (20487838747) 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, 1463416904 + ... + 1463416917.

It is an arithmetic number, because the mean of its divisors is an integer number (5853667644).

Almost surely, 2^20487836747 is an apocalyptic number.

20487836747 is a deficient number, since it is larger than the sum of its proper divisors (2926833829).

20487836747 is an equidigital number, since it uses as much as digits as its factorization.

20487836747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2926833828.

The product of its (nonzero) digits is 12644352, while the sum is 56.

The spelling of 20487836747 in words is "twenty billion, four hundred eighty-seven million, eight hundred thirty-six thousand, seven hundred forty-seven".