20281566736 has 20 divisors (see below), whose sum is σ = 39301195500. Its totient is φ = 10139322752.

The previous prime is 20281566731. The next prime is 20281566737. The reversal of 20281566736 is 63766518202.

It can be written as a sum of positive squares in 2 ways, for example, as 20141286400 + 140280336 = 141920^2 + 11844^2 .

It is a super-2 number, since 2×20281566736² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20281566731) 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, 27990 + ... + 203338.

It is an arithmetic number, because the mean of its divisors is an integer number (1965059775).

Almost surely, 2^20281566736 is an apocalyptic number.

It is an amenable number.

20281566736 is a deficient number, since it is larger than the sum of its proper divisors (19019628764).

20281566736 is a wasteful number, since it uses less digits than its factorization.

20281566736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182586 (or 182580 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 46.

The spelling of 20281566736 in words is "twenty billion, two hundred eighty-one million, five hundred sixty-six thousand, seven hundred thirty-six".