20651543316 has 36 divisors (see below), whose sum is σ = 52390994292. Its totient is φ = 6858993024.

The previous prime is 20651543299. The next prime is 20651543317. The reversal of 20651543316 is 61334515602.

20651543316 is a `hidden beast` number, since 20 + 65 + 1 + 543 + 31 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7559606916 + 13091936400 = 86946^2 + 114420^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20651543317) 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, 1025505 + ... + 1045448.

It is an arithmetic number, because the mean of its divisors is an integer number (1455305397).

Almost surely, 2^20651543316 is an apocalyptic number.

It is an amenable number.

20651543316 is an abundant number, since it is smaller than the sum of its proper divisors (31739450976).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20651543316 is a wasteful number, since it uses less digits than its factorization.

20651543316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2071240 (or 2071235 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The spelling of 20651543316 in words is "twenty billion, six hundred fifty-one million, five hundred forty-three thousand, three hundred sixteen".