20736774721 has 12 divisors (see below), whose sum is σ = 22458767232. Its totient is φ = 19138098096.

The previous prime is 20736774719. The next prime is 20736774733. The reversal of 20736774721 is 12747763702.

It is not a de Polignac number, because 20736774721 - 2¹ = 20736774719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20736774521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1495000 + ... + 1508806.

It is an arithmetic number, because the mean of its divisors is an integer number (1871563936).

Almost surely, 2^20736774721 is an apocalyptic number.

It is an amenable number.

20736774721 is a deficient number, since it is larger than the sum of its proper divisors (1721992511).

20736774721 is a wasteful number, since it uses less digits than its factorization.

20736774721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22720 (or 22707 counting only the distinct ones).

The product of its (nonzero) digits is 691488, while the sum is 46.

The spelling of 20736774721 in words is "twenty billion, seven hundred thirty-six million, seven hundred seventy-four thousand, seven hundred twenty-one".